Help?

Anslee

There’s a lot of detail here, so hopefully someone else has had the same issue and could possibly guide me. I haven’t gotten a period since the middle of October(2017), but 4 times since then I’ve gotten just a little bit of light pink bleeding as you do at the very beginning of a period, and it’s NOT around the time I would usually get my period. My doctor recently ran tests checking for PCOS and I don’t have that. He said my ultrasound looked totally normal, which is good and bad. Since I haven’t gotten a period I’ve been using an ovulation test kit and I haven’t ovulated(that I know of) in the month and a half I’ve been testing. My boyfriend and I have not used protection in 2 months, but my doctor also said 2 weeks ago that I’m not pregnant. Does anyone know what this bleeding could be from? Thanks in advance!