Potential causes for pain in the left lower quadrant include diverticulitis, colon polyps or cancer, inflamamtory bowel disease, or gastroenteritis.
Tests to evaluate this would be an abdomina CT scan - which can identify areas of inflammation suggestive of inflammatory bowel disease or diverticulitis. If negative, you may want to consider a colonoscopy to ensure there is no anatomical abnormality - such as a mass.
I would suggest a gastroenterology consult for further evaluation.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Thanks,
Kevin, M.D.