My boyfriend made out fully naked last Sunday. I gave him a blowjob and a handjob, which made him ejaculate for the first time in his life. I swallowed some of the semen that came out. My period is due tomorrow (I usually have a cycle of 28-30 days), and I've been feeling nauseated and my lower abdomen hurts for the past few days. What are the chances that I am pregnant? Please reply. I'm getting worried