12 DPO BFN

Ok ladies, I need your advice! Normally, my cycles are pretty easy since I had my laparoscopy a few years back. Meaning, no cramping, etc until the day of af. This cycle though, I have literally been cramping and having bad back cramping for the past 4-5 days. What gives? I took a test this afternoon at 12DPO and it was a bfn😔. Af is supposed to be here Thursday, so I guess I'm wondering what the chances are that I could still be pregnant, or if I should just move onto  next months cycle? I keep thinking af will be here any second, but every time I go to check she's not. My past 2 cycles were only 25-26 days and now I'm already on 27 this cycle. So frustrating! Anyone else going through an agonizing TWW right now?😩