My Period Started Feb14 And Ended Feb18 . My Boyfriend

My period started feb14 and ended feb18 . My boyfriend and i had sex on feb 20. He didnt cum in me he came on my stomach, on my stomach it was a puddle of clear stuff (pre cum i guess) then it was his sperm spread out on my stomach. I've been having headaches lately, is it a symptom or because im paranoid and stressing myself out