Discussion question!!

Ladies, quick discussion question! I’m about 2 1/2 weeks late, got a vf positive at home, went to the dr, turned out neg. That was a week ago! I’ve been very, very, verrryyyy tired. I can nap anywhere no matter what. Slight cramping but nothing like period cramps. No blood whatsoever. Anybody ever hear of a test not showing up until a couple months of pregnancy?? If calculating correctly I’d be about 6 weeks pregnant! Please give feedback as it is MUCH appreciated! Thanks in advance!!