Three weeks ago my boyfriend and I had unprotected sex. That was the first time in a month because I am away at school so we did have quite a bit of sex that weekend. Hate to be so graphic, but he DID NOT finish his business inside of me. I also take birth control regularly. I should have gotten my period on Monday, today is Wed. Today and yesterday I have had light brown spotting. Is this just because of all the sex three weeks ago or could i be pregnant? I have no other symptoms other than cramping. Also, Thurs-Mon I was so sick i couldn't go an hour without having to run and use the bathroom. Could the spotting be because my stomach was so upset all weekend?