So the other night (two nights ago now) I was having sex with my girlfriend, and my foreskin was pulled back beyond the head. I've never had that happen before and so I did some research into the subject and found that it was normal. Alright, alls good. There was a bit of pain, but I expected that, as my foreskin could now move a lot more than previously. My only real concern was that my foreskin would come back above the glans, but not completely, leaving just a bit of the end of my penis exposed. I did my best to push it back over (lightly, I wasn't forcing it) and it didn't work, so I left it, assuming it would return to its previous state of completely covering my penis.
I woke up this morning, and my penis is now back to normal, with my foreskin completely covering my penis, very tip and all. Except, its quite swollen. Its not painful to urinate or anything, but in general its just uncomfortable. I'm hoping the swelling will just go down if I refrain from bothering it too much, but I wanted to just be sure, in the case of this being something MUCH more serious. Looking forward to answers, thanks to all who reply. :)