Last week I had both a UTI and yeast infection. So I was on two forms of medication. If not on birth control I should have ovulated last week but had been taking them right and hadn't missed any. I had sex over the weekend with my boyfriend but he did pull out. Less than three days after we did I began to have slight cramping and light pink then brown discharge for the past few days. I'm a week out from having my next period. I know antibiotics can counter birth control so I'm wondering if this is my body adjusting back to birth control? I think it would have been much too soon for implantation bleeding and it was the first time that we were sexual since my last period.