Anyone had implantation bleeding and not been pregnant?

Driving my self mad, last Wednesday I have a good show of blood. It was 6dpo and it only came out nice and fresh as I was going for a number two lol. It didn't last long, 20 mins.. Then went.. Watery blood is what I can describe it as. Anyways I'm due my Af this Saturday but I'm worried I'm gonna get really let down as I'm not really feeling no symptoms no more. But I know things don't really start happening until 4 weeks plus. Anyone had implantation bleeding and not been pregnant?