Ok so I had a full month of cramps like worse then normal all of December then January I got period few days early now its start of march and I haven't gotten my period for February I was supposed to get it around the 22 and. I have bad lower abdominal cramps and leg cramps and feeling tired but nothing else. And four pregnancy tests are negative why is this if I had my tubes clamped 3 years ago? I got tubes tied when 21 please help