AF Missing and Frustrated

💗L
Well it is now day 37 of my normally 30 day cycle. No sign of AF at all. No cramps, boobs are not sore and no moodiness. I have taken three test all BFN. I called my doctors office and was told pee test are very sensitive and they didn't think I needed a blood test. My doctor also said that if the pee tests were negative then I'm not pregnant. I asked about my missed period and was immediately dismissed. Now I have no idea what is going on with my body and I have no idea when my next fertile time will be. Has anyone else had this experience or advice about how to figure out when my next fertile phase would be?