Anyone test 4 days before af was due and got bfn not even a faint line! But still was pregnant..... If so when did you get your bfp

AF is due 3/19 but I keep getting bfn....my breast keep hurting my stomach keep cramping....I had birthday cake and ice cream yesterday and it was nasty....I'm thinking AF is coming because of cramps but I been cramping off and on since 9 days before AF is due anybody had anything similar and was in fact pregnant?