My period comes every 28 ~32 days.. I have no idea when I ovulate.. I just have sex 12/14 days after my period. My period was on the 11th . And my period lasts 7 days.. I had sex on the 6th and 7th day.. so at the end of my period... ever since then, I have been feeling pregnant.. like, my heartburn is worse than usual, dizzy spells, and feeling extremely exhausted... plus I have sinus issues.. I do have some cramping.. I'm thinking maybe I ovulated around the time my period ended?