implantation or early AF ?

Started some red spotting only when I checked my cervix would I find it 5dpo; yesterday same thing 6dpo and now today(7dpo) this is what I have when I check. Could this be implantation or early AF? I'm due for AF on the 20th. I have having mild cramping for the past 2 days and sore sore boobs since 3dpo.