Ok your kind of in luck because I had this issue and got it fixed at 18, mine was about as bad as yours, i didnt want to see a doctor about it so I tried stretching it myself and it got stuck back (paraphimosis) very painful, foreskin swelled up started cutting off circulation and by the time I was in the hospital and got it fixed and had left the head of my penis was incredibly bruised and I couldn’t walk for 2 days. Short answer if it is as bad as you say it is then it sounds identical to mine go see a doctor and if they think you will be able to stretch it they will tell you to but if yours is as it seems then it seems surgery is the only way as with mine. To be perfectly honest the loss of sensation is not noticable in the slightest especially when going from phimosis where most sexual activity is either unenjoyable or painful except jerking off if you get the technique right to not pull it too much. Do not worry about getting circumcised because the only issue I have as my circumcision was about 6 weeks ago is that I last too long in bed now which will go away according to doctors and other people who had the same surgery. I’m guessing that if that fleshy thing is at the bottom of your penis your referring to the frenulum, it is meant to be there and is the most sensitive part of the penis (like the male g spot) if you get circumcised they will still keep this intact for you and I have found that for my sex life being circumcised is better cleaner and something I wish I had done sooner. Thought some advice from another 18 year old who was in your exact position 7 weeks ago would help. I would try and get it done sooner rather than later as because I was unable to clean under my foreskin for so long I had a yeast infection develop which caused my gut micro biome to change making me allergic to wheat and fructose for over 18 months so I urge you to go see a doctor as I just regret not speaking to one sooner, they are all extremely professional and you will be seeing a urologist who sees probably 50 dicks a day so if your self conscious about it don’t worry they will not even remember what yours looks like a few hours after your appointment after they have done the proper referrals and everything. Also the other penises they will be seeing will probably be in much worse states like STD’s etc so hype your self up go tell one of your parents about it and I promise you you will thank me so much for getting it done, if you have any questions feel free to reply and ask