I had unprotected sex with my boyfriend about the 12th of October, about a week after my period. I'd been taking birth control regularly, and I missed on pill that week, and one or two more that weekend. (Yeah, it was stupid to not use extra protection. >< ) My periods have always been regular, around the 4th of every month. It's the 10th and I still have no period. I took two HPTs and they were negative. Could I still be pregnant if the home tests were negative?