I'm 11 dpo and I really thought this was my month. I was really upset earlier when I wiped and seen very light pink blood. But I read somewhere that implantation bleeding can happen all the way up to 12 dpo, is this true? AF is due the 31st and is usually always on time, never late or early. And usually when AF starts it's very heavy, with little to no spotting before. I have some cramps on the lower left side of my stomach but other than that nothing has been out of the ordinary. Could this be implantation?