so the last few months , my periods have been pretty regular . starting around the same time and lasting the same amount .Well this time, I was spotting 2 days before my "start date". usually when i start, Its so bad that I have blood clots cuz I have endometriosis but this time it's on and off ! It's not heavy at all like usual and it's spotty ! I took a test 2 days before I started spotting the first time and it was negative ! has anybody else experienced this ?