Hello, I Am A 54 Year Old Female. I Have

Hello,
I am a 54 year old female. I have been having mild lower belly cramps off and on. I visited my Ob-gyn 6 months ago and found nothing wrong. The cramp is similar to menstrual cramp. The cramp itself is not so bad but I feel weak and feel like fainting when the episode occurs. I am otherwise healthy--workout 4-5 days a week, eat healthy, sleep 7-8 hrs/day.

Thank you in advance for your input.
Christine