My AF was due nealy a full week before the end of my 2WW, Thats how it is every week for me, So at first I was testing when my AF was due and constantly getting negatives, this month i waited the full 2 weeks and got my positive, maybe it pays off to wait the extra couple days i'm not sure.. But that i something i just worked out today, My AF being a week early then my 2WW.. I don't know if everyone else is the same..