So I started my birthcontrol again in the middle of June. I take the pill mercet. My period usually starts on the 25th of each month. Well I know that of you start BC again it can change when your period starts. I also was taking anti biotics for my bronchitis that I had as well. We have had sex 3 times all with out condoms. My period still has not started. I spot then it goes away then comes back a few days later. I took a pregnancy test July 2nd but it was negative and i don't know if it was too soon to take one. Could I be pregnant?