Hello and welcome to HCM, Pain abdomen which is localized to the left side, associated skin rashes, and increased frequency of bowel movement could be due to inflammatory bowel disease, irritable bowel disease or infective bowel disease. All these disease entities are dissimilar to each other with different modes of management. First of all, you need to get a stool exaination done- routine and culture. This test will identify infection if any in the GIT. Malabsorption and blood in stools will also be identified. The second investigation is GI endoscopy. In this test an endoscope will be inserted in the GIT to look for any mass leson, or any other abnormality of the GI tract. Contrast studies (barium enema, barium follow through) may be required depending on the clinical features and dicretion of your treating doctor. Consult a gastroenterologist for clinical examination, relevant investigations and management. Thanks and take care Dr Shailja P Wahal