Implantation bleeding or AF?

6 dpo (ovulation confirmed by positive OPK), starting bleeding last night around 11. Started off brown and now it's a bright red. No clots yet and no cramping. No usual AF symptoms just bleeding. Not very heavy either, can't even fill a light tampon in 6 or so hours (going from when I put it in last night to when I woke up this morning). Tested Saturday got a vvvvvvvfl.