Is it normal that i did sexual things with my cousin?

Ok, so when I was atleast 5 years old me and my cousin where playing house in a corner. I know, wired right? I was 5!! Anyway, he began talking to me and said that if we want to play house the right way, we have to do grown up things! So, he then told me to take off my pants and I did so! And now that I look back at this it's weird, how did he know all these grown up things? I mean he was a year younger than me!! As I was saying, I took off my pants and he began kissing my..Uhm..well I think you get it! He then told me to touch his..Uhm..yah, and I refused to and said I wanted a devorce! (I was 5 and playing house). Then when I was 13, he came over a week after the fourth of July. My younger brother wanted to play house, So we did. My cousin them got close to me and asked me to makeout with him. I told him no, were cousins and I like someone else! He told me to imagine him as the other guy I liked. And well, I did and we began to makeout! The worst part is that he was dating my bestest best friend at the time! I called her and told her what happened Nd she forgave me. But the reason I told you this is because I want to know if it was really wrong for me to do this?! And I'm not sure if he's my second or third cousin..so yah!