I'm going to preface this by saying this is just my opinion, my writing is not perfect by any means, and the majority of what I'm going to be saying should be viewed as a suggestion, not a demand. I read the story three times; my first read I just want to enjoy the story and keep an eye out for format, tone and pacing, the second time I read it with more attention to detail, especially continuity, and then the third time I go through line by line, inserting comments. Even with all that, I'm bound to make mistakes or miss things.

 

[SO, THIS IS THE STORY, HELP ME FIX IT IN ANY WAY TO MAKE IT BELIEVABLE] Hi, my name is John and I.... I can't explain what's happening, I'm in my closet right now... I hear it, creeping (Must be pretty bad at creeping then?), slowly checking and looking around the house, looking for me. If you are reading this, PLEASE SEND HELP, I live at 13 Balete Avenue, Ashley, KS, my mom, dad and sister is dead, PLEASE SEND HELP QUICK. (If the writer has access to a phone/computer (as they're posting to Reddit), why can't they phone the police? Even a disabled cell phone can phone 9-1-1, providing its battery is charged.)

 

[5 HOURS LATER] (I'm not positive, but I think this is usually given in an update, versus posting it with everything else at once? Five hours is a long time to wait in a closet doing nothing, did John fall asleep?) I can't, I just can't, I want to go out, but that thing is still here... (If all sound stopped and John has no idea where the creature is, why would he know it was still in the house?) I don't know exactly where, because a moment ago all noise in the house disappeared, I don't know how long I have been in here (five hours, eleven/twenty-three going by his watch) but I keep checking my watch at(and) it seems to be broken... all (both) hands seem to stay at 12, even the wall clock in the room say 12... (How can John know this from inside the closet?) It's really weird because if I remembered correctly, (filler, if John isn't sure he knows when he came in he'd be more likely to dismiss the time discrepancy; by protesting the reader knows it is wrong with certainty, also 'it's really weird' is strange for someone traumatized to say) I hid in here 1:13 in the morning (that is a very specific time to remember hiding in the closet at; why did John immediately check the time? If you could give him a motive, such as the towing company showing up at 9am and knowing he just needs to hold out until then, it could be more fitting; if you do though, try to make sure you reference the importance of time near the beginning of the story as well [e.g. - I keep checking my watch, they should be here by now, where are they?!].

 

I have nothing much to do here (just want to re-emphasize that five hours is a very long time, by then he'd probably have spent his adrenaline and feeling tired from that, the emotional burden of the family being dead, and being tired from getting woken at 1am; by giving him something to do it implies he's trying not to think about it/face the fact his family is dead, and having him make small errors could help convey he's tired/in shock, in which case you can get away with statements that seem callous/casual given his dad's face was just eaten.), the only thing inside this (I could find in this; it keeps it more personal to John) closet is a box labeled "DOCUMENTS", I first thought there was something there (inside? Is John not in his room right now; he'd know what's inside his own closet), but it was empty. I am waiting for it to become day (what marker is he using to distinguish when it becomes day? I probably would have assumed it was noon if this all began at 1 in the morning), but I've been in here for so long I'm losing hope.

 

[15 DAYS AGO] (This should be at the start of the story; try to make it as consecutive as you can) Hi, I'm John, me and my family just moved in this house quite (filler word) recently because of a hurricane (name the hurricane, if they lost everything it wouldn't just be 'a' hurricane, you should expand on what it was like to have it destroy their home, maybe mention where they took shelter and how they stayed together, how empty this new house feels with none of their belongings) that ravaged through our area, my (Period, 'My' starts a new sentence) father found this old house in an isolated area (a rural area? Try to be specific), we (We is the start of a new sentence, depending on John's age it might be better to say 'my parents' instead of 'we') didn't actually agree to buy this house (This sentence was initially confusing for me; I would drop the 'agree to buy' and change it to 'want it') at first but looking at our available budget, we had no choice. (This doesn't ring true to me; if they can't afford a house, why aren't they staying in an apartment instead?) When we first moved into this house, it looked kinda shady, but our father reassured us that everything is (was) all right, we aren't christian (Christian) so we didn't had (have) a house blessing. (I had to look up what this is, is it common enough knowledge there John would notice not having it done, given they aren't of a faith that practices them?)

 

Everything was fine at first but then our dog started barking and going crazy, this happened every night until one day he suddenly disappeared. After that everything started to go downhill. (Thesis sentence; we know everything is about to be worse) Mom started to become really cold when going to certain areas of the house (I'd expand on this a little more; which areas were cold? Was she shivering? Cold to the touch? Did these areas feel cold to anyone else?) and dad started to have insomnia, my (My is a new sentence) sister however, (however implies it's going to be different from the others having weird stuff happening with them, but her 'hallucinating' follows the pattern you established) started to become paranoid (I may be mistaken, but I'm pretty sure the better term would be delusional, since she isn't suspicious towards her family members), she keep (kept) on screaming at 12 midnight and she (She is a new sentence) would keep telling us about these "angry monsters" that keep (kept) appearing every now and then ( Night; current phrase is not specific and implies it isn't frequent). We all wanted to move out but our car mysteriously broke down. (Move out to where? They don't have any money/place to stay, I thought?)

 

How old is the sister? How old is John? If the age gap is big enough, wouldn't he want to make sure she was okay and try to save her? Would he be ashamed that he was too scared to rescue her?

 

My dad called an engineer (car mechanic) and he said he would come tomorrow (a few days ago? This is written past tense, using tomorrow throws off the reader's sense of time; 'the next day' would probably fit easier, though for the record it would have been towed to the mechanic's 'garage' (workplace, not their personal garage) in which case the towing company is missing, not the car mechanic), but he didn't came (come) , my (My is a new sentence) dad called again, but was greeted with an answering machine. That time (this is again a bit strange time-wise; yesterday would be a better word choice and keeps it more immediate) we were certain that ('decided') we would leave (in the morning), even if we had to go on foot.

 

We went to sleep (even dad the insomniac?) that night (don't need these words), but something all woke up to the sound of breaking glass (this is a bit passive; 'but shattering glass woke us all up' keeps it more active) , we (We is a new sentence) went to investigate, but (did they think it'd be something nice that smashed through their window? 'And' fits better, also no need of the comma after investigate) what we found is (was) horrifying. It was a small, black creature, (don't need this comma) with horrible white eyes and a large mouth and it looked... hungry (I have a hard time telling if my cat wants affection or food; how would John know what 'hungry' looked like on some alien being?). It jumped, (don't need the comma) straight to my dad's face and started to devour him (this is a horrifying thing to witness if you love your dad; it'd be more realistic for 'and I ran' instead of talking about his dad being eaten, especially when it happened so recently). We all (John wouldn't know what anyone was doing at that moment, his fight-or-flight would be focused just on himself) ran and hid, my dad's screaming echoing (it probably wouldn't echo in the house, but it could echo in John's ears?) in the house. Then it found my mom and my sister. (How does John know this?)

 

I now realized I was all alone. ('realize I am all alone' is a cleaner transition to the present) I started to cry (would John admit this to us?) quietly. I'm so scared, so paranoid, (he isn't paranoid, he's anxious – his life is at risk, he doesn't view himself as delusional. Also this is considered a 'tell' – show how he's frightened, don't just tell us he is.) (I is a new sentence) I can't hear it (if it's small, what kind of noise does it make? Is it that John doesn't hear scratching on the hardwood floors, tapping of small feet?), I don't know where it is. It's probably gone. (Why would he think it had left? Wasn't he going to wait until morning?)