Can i get some advice?

Af was "due" on tuesday. Af still hasn't shown up. I haven't tested since Monday because that test was negative. Don't wanna waste money for what I know will be negative. I have been cramping on and off like af is coming. This morning I thought I started because I felt something leak out of me and when I checked, it was white cm. So I checked my cervix and there was brownish blood tinged in with the cm. Of course I haven't heard back from my damn doctors office.. any idea on what it may be? I have zero pregnancy symptoms!