Twerking

So i went to this party and it was dark. They were playing music and everyone was twerking. A girl was twerking and my boyfriend went behind her. One of my classmate told me my boyfriend was not loyal. My friend told me to go to my boyfriend and "claim him". So I did but I was still very upset about what happened. So I ran to the bathroom and my friends ran after me. I started to shed a few tears and I felt sick to my stomach. My eyes were red so I had to avoid any of my classmates and boyfriend. My boyfriend apologized since I told one of my friend and he went to go and tell my boyfriend. I don't know what to do since I can't necessary trust my bf. What should i do? (We are in eighth grade)