Hi, I'm 16 and I've been having some problems, a few days ago I knocked my penis by mistake on my jeans while it was erect. It seemed to hurt a little at the time but I haven't really had any pains. I went to the toilet for a pee that night and it was fine, but the next morning I went and a small part of it was very dark, almost as if there was maybe a small amount of blood or something like that. Although this hasn't happened since and it's been quite normal.

I've not particularly seen any physical problems, although I'm unable to pull my foreskin back properly anyway to check as it's too tight. Thats a problem I've had before this.

It's still feeling quite tender and I can feel it slightly sometimes where I'd knocked it, but the main problem is that I haven't had an erection properly (although the day after it happened I did seem to have an erection like normal) but since then it's either only gone up half way or I've got a full erection but it only lasted a few seconds.

I'm considering going to the doctors, but would like any advice that I can before I do. Thank you.