Okay, so, I haven't had my period yet. I'm on the Nuva Ring Birth control. I took it out on Sunday the 1st and i usually start my period the following Wednesday. It's now Friday and it still hasn't come. I took a pregnancy test and it came back negative. The thing is, i just got over a UTI and Kidney infection and they put me on a couple different medications. Could the medicine be causing my late period?