Why do I get cramps before I have my period? My period isn't supposed to start for another week or so. I seriously think I have IBS. I'm constantly in pain, have constipation or sometimes diarrhea. The pain usually comes after I eat (which is part of the reason why I don't eat - because I'm scared). I always knew I had a bad digestive problem, but now there's blood. :( I don't have medical insurance yet so I don't know what to do.