I am 18 days late I took multiple test until 8 days late all have been negative . My boyfriend and I have been TTC for 4 months my period had been 27-28 days since coming of birth control in July. I have PCOS and Endometriosis but I have never had the irregular period parts of them at most a couple of days never almost 3 weeks . I have had some slight cramping but not like the pain i usually have with cramping . I have had some stomaches, dizziness, costipation and have been very tired lately. Is it possible that I could be pregnant and it not register on the HPT? Should I go to Birthright and get a test done there ?