anal sex

I had sex tonight and it was with my bestfriend, he wanted try anal because he never done anal. I have done anal once before and I didn't really like it but I didn't hate it. Me and him has had sex multiple times together but as best friends, so he wanted to try it. So we had anal sex and when I went to us the restroom, my butt was bleeding a little and I have a very uncomfortable pressure on my uterus and butt and I kind of freaked out a little but the first time I did anal, I didn't bleed. Is it normal?