I have been on birth control for 10 months. Last week, on the third week, I missed one pill and took it when I remembered which was 15 hours late. I finished that week taking the hormone pills normally and had sex 3 times without extra protection. I continued taking the birth control normally including the sugar pills the following week. My period didn't come and it is 2 days late. I already read that I should not had taken the sugar pills, instead start a new package, so now that is too late I want to know what are my chances of being pregnant? Should I worry about it much?