I am on yasmin contraception and i am currently taking trimethoprim for a uti . I had unprotected sex 2-3 days before i started the anti biotics but my bf didnt finish inside me. I woke up this morning with a small amount of blood in my urine ...i have only started my new pack of yasmin pills in the last week. Does this affect the pill and the unprotected sex from before i started the antibiotics?