Love & sex

So there was this guy that he always looked at me weird but like it's a cute weird that I found out he likes me and I always liked him but the problem was that I had a boyfriend that hated him so we only talked at school. But then I found out my bf was cheating on me so we broke up two days ago. I went to smoke weed last night with friends and the guy was there. (Don't judge about the smoking I know I am only 15) We were in his vehicle and he just got done and passed the blunt and he just grabbed me and we made out for at least 3 mins. After we were done smoking we all got out and went to another vehicle to go home and my friend and him called me over there. So I went not thinking anything bad, but he asked for a hug and they grabbed my butt then he took me over to his truck door and kissed me then put his hands down my pants.... I didn't know what to do so I just let it happen then I told him I had to go so we all left. He message me after saying he wants to hang out tomorrow which is today and I didn't answer I was to scared to.

What should I do is it wrong to get with someone after I just broke up with a guy but the guy cheated on me so idk.....