I regret having sex, how can I get over this feeling?

Me(14m) and my gf(16f) had sex about 2 weeks ago. She didn't really force me, but I definitely felt pressured. I didn't enjoy it and i've been really down since.. I feel dirty. I assume it's not typical for a guy to feel this way after sex so it's pretty embarrassing to post this. If anyone has advice to get over this feeling, I'd appreciate it. 👍🏻

Edit: I know for a fact I am not gay, I am attracted to only girls. I just think that I had sex before I was ready to do that kind of stuff.