Implantation Bleeding ???

Help ! Need advice ! So I skipped my October period and went to the doctors in mid November and he prescribed me Provera, so that helped start my period on Nov 13-30th. I have now completely missed December and three days ago I had some light spotting, not enough to fill a tampon or liner, until today and it’s completely stopped. I tested on Saturday but it was negative. Any idea what about might be going on ?