Need some advice TMI

So AF was 2 dad late. I usually get premenstral cramps to let me it's coming. I woke up and it was bright red with brown discharge and a lot of mucus. It was kinda heavy at first with some mild cramps. Usually  my Period the first day It star off light and heavy cramping. Then it got light and now today it's brown. My period is usually 4 days and today is the second and it's brown. Was it AF or implanting bleed!?!