I Started My Menstrual Cycle Yesterday. The Past Week I

I started my menstrual cycle yesterday. The past week I have been having periodic flutters in my abdominal, and it has been all over in different spots, not just in one place. I also had the worse nausea yesterday, and it has been lingering today as well. What could these flutters be? I had horrible morning sickness with my 19 month old son, and had some flutters in my early pregnancy with my son. Could I be pregnant even though I am on my PMS?