Hi and welcome to HCM.
There are various possible causes but common are diverticulitis
, IBD or pelvic organs disorder if you are female. But it can be caused by any lesion in abdominal wall like muscle pulling, abscess
. YOu should do ultrasounds to rule this out. Also try to find is pain triggered by certain food and then avoid it. If nothing helps then endoscopy
should be performed. Wish you good health.