Ladies i need your help?

my last period started oct 24th. my cycle is all over the place. last months cycle was 26 days. so i went online and an ovulation calculator said my fertile days are nov 2nd to nov 7th. i had with my fiance nov 2nd and 3rd. a few days after i started have cramping, twinging and tingling in my uterus, headaches, and dizzyness oh and bad gas. ive never had symptoms like this before and im 25. what is going on?