Suggest Treatment For PMS

Okay I dont think I am pregnant but 4 weeks ago I had sex. But got my period like 1 or 2 days after that. IT was normal My period should be in 4 days. I think i have PMS right now. I have no reason to be pregnant since he didnt cum in me or at all. And I am on Yaz. Am I just over reacting and scared fro ma last pregnancy scare?