Two days after the start of my period, I get very bad stomach cramps and diaheria. This has happened the last two periods. Prior to this I had some unusual cramping between my cycles. I went to my doctors and she did an exam and said that my ovaries felt fine. I am concerned that these are symptoms of something very serious. I am 37 years old and have four children. The last two were twins and they are now five. I generally get my period every 27 days and it is heavy on the second day and lasts 3-4 days.