R low abdominal pain that is severe after eating. I know I cannot get a diagnosis here but I am nervous about cause. Losing weight with nausea?

Bowel lesion. Loss of wt and pain on eating with nausea is related to some form of bowel pathology. The may be an obstructing lesion of colon or an inflammatory lesion. Should be seen by gastroenterologist to have colonoscopy follwe by abdominal scan or PET is tumor detected. Tumor markers also need evaluation if monitoring results of treatment required.