Anal by Accident ?!?! 😳

Caty
So my bf and I were having sex and yeah things were getting intense and he was giving it to me from behind. Anyway we were starting to go harder and he went to slam in to me but he accidentally missed the spot and instead gave me anal. 
I have never done anal before, so to get his full size slammed into me, without any sort of prep or anything, it was so painful. My bf felt so bad but I kept reassuring him it was ok, it was an accident.
The pain was really bad for a couple minutes but it's not too bad now, like it's still a bit sore but it's not excruciating. 
Just wondering has anyone else had a similar experience and what happened with them afterwards. I guess I'm just kinda worried something may happen because I honestly don't know what to expect now. Help me please😧😧😧😧🙏🏼🙏🏼🙏🏼🙏🏼🙏🏼