I give up this cycle ugh

So I've been cramping for an entire week with no af. I have no idea when she's truly due since it's my first cycle off the pill. I was on the pill for ONLY 4 months. I am on CD 27 and the longest my cycles have ever been are 30 days but that was before I started taking birth control. On the pill my cycle days were 22 to 23 days long so technically I am late. I tested yesterday and got a bfn. I know I am being impatient but it just sucks because I never cramp with no af unless i'm pregnant but the tests keep showing negative. If I am not pregnant I just want my damn period to start. Ugh :(