I have been on the combination pill, Mononessa, for going on two months now. I have never missed a pill nor been late to take a pill. I am now seven days into my second pack. I had my period during the week I took placebo pills. I have unprotected sex with my boyfriend, but he never gets off in me. I have felt nauseous on and off this week, and my breasts have been tender on and off since I started birth control. It has been a week since my period ended. What are the chances of me being pregnant? And can birth control make you nauseous to where you throw up?