I have always had slightly irregular periods but never missed more than one month - always typically start within a few days (but not exactly 28 days apart). Typically very heavy, terrible cramps. I had a tubal ligation surgery 11 years ago after the birth of my daughter. I am 38 years old. In January we participated in Whole30 diet and I had the lightest cramping of any period that month which I assumed was maybe related and I was grateful. I did not have a period in February and typically I would have started a couple days ago if I was to have a cycle in March. I have no symptoms of pregnancy, but I have not taken a pregnancy test but I am all but certain that is not the case. With the assumption it is not pregnancy - what are some other things? I do plan on calling my doctor tomorrow.