False positive.

Okay. So I have a UTI and I took a test while using AZO. On every websight I looked at , it said it wouldn't alter results. 
This was my test. We've been TTC. I was so happy. Took a digital and it said not pregnant. Waited a few days till the AZO was out of my body. Got a BFN. And today I got my AF. ?stupid AZO