12 days late BFN could I still be pregnant?

I am 12 days late today. The last test I took was on Saturday 9/29 and it was Negative. I am not bleeding nor am I spotting. I am having some cramping, but it’s a not like my regular menstrual cramping. My OB says to wait till I’m 2 weeks late then I can do a blood test. Has anyone been this late before with a negative pregnancy test and ended up really being pregnant?