is this even possible?

Okay, I'll start off by saying I was recently diagnosed with Hypothyroidism and PCOS, and my dr put me in birth control until I can get the thyroid levels situated. I missed a month of birth control back in September because something came up and I could only get my thyroid medicine. We ended up having a chemical pregnancy. Well now I've been taking my birth control without missing any since then. I also had a bladder infection this month and was put on antibiotics, but my husband and I didn't use any other method of contraception because I dont think it could have happened with my issues. But here I am on the 3rd day of the sugar pills at the end of the pack and I haven't got my period yet even after cramping all last week. I'm definitely getting a test when I go out later to ease my mind because I'm showing a ton of symptoms but they could all be symptoms of Aunt Flo as well. Has anyone ever had these conditions and ended up pregnant?