Could I be pregnant

So I started spotting on Saturday like really like pink only say it cause I was checking my cm. On Sunday it started being seen when I wipe so I figured ok hey start of my period and then today it turned red so I put on a pad but by mid day it was barely full and the blood look kinda brownish the pad never filled up except maybe quarter of a way all day now it seems like it's going away when I wipe I see it but looks fading I'm tired and dizzy a little but have been pregnant before don't feel pregnant now took a pregnancy test BFN but I don't know my period wasn't actually due til Wednesday so it came like 3 to 4 days early. Any insight anyone