AF was due 6/19!! Need Advice.

Ni
Currently 16dpo with EWCM. AF was due 6/19. I'm currently 3days late and I had horrible cramps yesterday 15dpo and expect to see AF this morning because of the horrid cramps!   however, no AF, BFN and EWCM that's cloudy white not clear! 
Could I possibly be implanting late? 
Are there any ladies who has experienced this before?