Another thing to add is that I usually have sore boobs just before O and continue until AF arrives. My boobs became less sore day by day and were completely not sore on the day of the bleed. With so many evidences against me.....i was pretty worried.
I also thought that implantation occurs on day 6--10 after O so I was expecting the bleed to occur between that window. That's day 11 for me.