bleeding during sex

My partner and I hadn't had sex in about a month. We then did it on Thursday everything was fine. He came and saw me today because I'm staying about 3 hours away. I've had a little bit of binge weekend with alcohol. I'm on the pill and iron tablets. I've never had this problem before. But we were getting a little intense and he was being a little rough and deep. All the sudden we realised there was blood and it was from me. Is this normal? Should I see a doctor? I'm a little bit sore there but it's nothing major. 

I know this is a little gross and has a bit too much info. But I'm sure there's someone out here that knows something.