Boobs hurt and stomach cramping

My period was from the 6th-10th we had unprotected sex on the 15th once. But my boobs have been hurting since the 19th and I don't know why only when I push on them a little and my nipples are killing me. I keep having cramping in my stomach on one side and its been doing that for over a week. I don't think it would be pregnancy since I've hears you can't get pregnant right after menstrual cycle?? My next period is due around the 6th. Should I wait it out and see?