Brown discharge...then pink/bright red spotting


Please help Glow fam!!

I’m supposed to have AF in 4 days, but today I woke up with light brownish discharge and slight cramping. My SO and I had intercourse and now there is a bright red/light pink spotting. Not even enough to fill up a pad, just when wiping/a little on panty liner.

Could this be implantation bleeding or just AF visiting sooner than normal??