Hi thanks for asking question. Left side lower abdomen pain usually due to colitis , diverticulitis or gas accumulation. Here in your case pain could mostly be due to constipation. But still to rule out other causes like diverticular disease or obstructive lesion perform USG scan or x ray.If needed colonoscopy also can be done. Meanwhile to relieve constipation..... -Drink more water -Avoid excess tea, coffe, smoking, alcohol -fruits more -green leafy veg more -fiber containing food useful like apple, wheat bran , whole grain , banana etc. -avoid gas forming food like cabbage, cauliflower etc -digestive enzymes or fiber supplement can be taken. -chamomile in tea can taken. I hope my suggestion will be helpful for you. Happy to help you further. Dr.Parth goswami