what could this be?

im 16, My boyfriend and I have been having sex. (dont need "hate" comments) But two days ago we had sex, i was riding and he went way to deep. We had to stop because it hurt so bad, as if it was a period cramp. I just got off my period and was suppose to start it on June 2nd. I woke up the next morning with severe lower abdomen pain and bleeding. Plus my boobs have been sore. We have had sex 3 weeks before Wendnesday night.