My boyfriend and I had sex and the condom broke during but we didn't realize until afterwards. I am on Yaz birth control but have only been on it for a full cycle. I also am worried that my antibiotics (Sulfameth/trimethoprim) that I stopped five days before the sex, may have interfered with the birth control. I had just gotten off my period when we had sex, and was on Day 5. Should I be worried about being pregnant? Should I take Plan B?

No I think your OK.Get checked out just to be safe.