What Causes Stomach Cramps And Vomiting During A Menstrual Period?

Hello. For 3 days prior to my period & for the first full 24 hours of my period (so far), I've experienced severe cramps, nausea, vomiting, and loose stools. Earlier this month, I also experienced severe cramping for one day on my left side (the timing matched with what likely was ovulation). None of this is normal for me. Usually, I just have one day of bad cramping at the onset of my period. I understand that cramps usually lessen after having had a child (I had my first baby in Nov 2009) and am wondering if I should be concerned & try to see my OB soon (I currently have an appointment scheduled for the end of March for an annual, but should I try to get in sooner?). Thank you.