HELP A SISTER OUT PLEASE

Hello, I’m 14DPO , AF was due yesterday (13DPO) but hasn’t come since, I noticed a light brown blood as I was cleaning home girl with my fingers, howerer it was first milky white discharge that saw on my fingers and when I went in again I saw the small blood. I’ve had cramps for the past 4 days straight and lower back pain. I got a BFN at 12DPO.

This has never happened to me before.

What could be going on?