has any1 had a late bfp?

im not sure if im posting this in the right forum but.. has anyone had a bfp a few days + after their af was due, im asking this because i normally have af every 2 weeks when i was breastfeeding my 5 month old but i stopped breastfeeding 3-4 wks ago and havnt had af yet so i tested today and was bfn this would have been 2 day after a regular 28 day cycle...also im not sure at all when i would ov, so would bfp show? so confused, sorry for the long post xx