Cramping Without Period

Hey everyone! AF was supposed to visit this past Sunday, 12/11. I have been cramping somewhat like I could start my period at any moment. I've kept track of my periods for the last few years and cannot recall being late ever. I took a pregnancy test (the cheap ones from the hospital) and it was super negative. I haven't taken another test since then. Was just wondering if anyone else has experienced this and ended up pregnant?