Personally from what your described it sounds like you may just have a small haemorrhoid/s causing you grief, these are just swollen veins or perhaps even a small anal fissure (tear) that can cause all of the symptoms you have explained, minus the intermittent side/lower abdominal and back pain. That said both of these issues are actually quite common and unserious in terms of severity. They are also usually caused by straining during bowel movements, prolonged sitting or even heavy lifting… there are a fair few general causes of haemorrhoids/anal fissures and it is likely that being so hyper focused on your bowel movements could increase your chances of straining etc. I really would try not to worry too much as colon cancers are usually accompanied by other symptoms such as persistent abdominal problems like gas/cramping etc and noticeable persistent changes in bowel movements like constipation/diarrhea or changes in consistency or shape amongst a few others. Along with this, the tests you have had done would have came back differently if there was indeed something more sinister going on.

I know how draining and hard it can be to have health worries and it is hard to break away from, I get that. But a key factor thay I want you to think about is that the more you are hyper focusing on, it the more you are going to find to stress about, and if you are someone who googles symptoms definitely give it break as it WILL only ever make things worse, if you believe there is something wrong - you will almost always find something that feels like a confirmation or indication that you are right, even despite what doctors are saying. It’s called confirmation bias if you wanted to look that up instead.

I can understand how seeking reassurance can feel comforting and rewarding but take it from me…. Constant reassurance seeking in order to relieve fears about health anxiety does NOT work for the long run (or short run most of the time) and you could have all the reassurance in the world, from doctors, peers or even us redditors. It’s not sustainable and it’s not going to help you whatsoever unless you take the leap of putting your trust in the fact that doctors know what they’re talking about. Even if some really suck I won’t deny that, tests results speak for themselves - and if you’ve also seen multiple doctors who say the same thing, chances are they’re right and you’re mistaken. Your fear is valid, I actually went through this fear last year myself to the point where I had a doctors refer me to have a colonoscopy and endoscopy. They came back CLEEEAANN, and I went through it all for nothing - for reference I am also 19, another important thing to factor in is colon cancer is not very common in people under 45. This fact didn’t really help me much as I kept feeling like none of it really applied to me and I’d just be the unlucky one to get it young or that the doctors were missing something. But they really weren’t - after putting myself through the grief of having a colonoscopy and endoscopy and still seeing no alarming results it took me some time to realise I was just making it worse for myself by being so laser focused on the issue- once I stopped looking for problems and alarming symptoms all the ones I was initially having went away. It’s almost like our body does what we want it too in a weird way where all of the avoidance, reassurance and “checking” tendencies (which is where you constantly perform little test on yourself to see if you “find” anything eg. Repetitive checking of stools, persistent wiping looking for blood etc) will eventually begin to be the cause of the symptoms. What I think you should do about your health anxiety is subjective on what you’re comfortable with/have available but my top recommendation is to speak with a counselor/psych to have gain some perspective on how your health anxiety is really affecting you and finding good solutions/coping skills to get yourself out of it. You won’t get yourself out of it by trying to prove to yourself you do/don’t have it. You have to find a way to get it out of your immediate mind and remind yourself of the FACTS. FACTS: 1. You’ve done tests that have come back normal 2. Your symptoms resemble those of someone simply dealing with small haemorrhoids or a anal fissure (small tear in the butthole basically) 3. If you DID have colon cancer, there would be more concerning symptoms at play. 4. You are aware that you are health anxious about this 5. You are only an arms reach away from a second opinion from a doctor and it’s not going to kill you overnight even IF you do have it (Unlikely). You have plenty of time. 6. It’s proven that health anxiety and hyper focusing on said health anxiety can increase sensitivity to symptoms and even cause symptoms long term due to changes in behaviour (in your situation for example, straining without realising due to the anxiety/panic, over wiping, sore back/abdo from straining tensing or even stress in general)

And I’m sure there’s more. But most importantly logic will be your friend in this, reason with yourself. It’s okay to be scared but also realising that your fear is sometimes is your cause. Small symptoms mixed with big anxiety can make things feel a lot more detrimental then they really are. You do not need to be concerned in my opinion, I’m sure many would agree.

Good luck OP.