I had some light brown spotting on day 19 of my cycle, light brown/pink spotting on day 20 of my cycle and light brown spotting on day 21. It stopped after that. I’m not due for my period for about 8 days from now. Could this spotting have been implantation bleeding? I’ve had a slight headache for a couple days, and very light cramp feeling but hardly anything and a bit of nausea.