Idk, this sounds a little rapey to me. You pushed him off you continuously and tried to literally run away, but he kept grabbing you and forcing himself on you? Everyone is saying it reads like a romance novel, but I don't see you really even enjoying it, just making it through. You feel shame as if you made the decision to fuck him, but it seems like he made that decision for the both of you.

Own it man. The best thing you can do is absolutely and completely own it. Respond to the guys with "well at least I'm not the one with another man's dick on my phone" and to the girls with "you jealous?" or some other snarky comment. As soon as you back down, they will pounce, so hold your own