Hi. Thanks for your query. You pain in the left lower side of the abdomen may not be related to the menstrual cycle as this is only 2 nd day of your periods but you have pain since 8 days. The most probable cause of such a pain on the left lower side in a female patient can be : Colitis. Salpingitis. Ovarian cyst I would advise you the following: Get a Physical examination of the abdomen done by a Surgeon. Get an ultrasonography and S-ray of the abdomen in standing position. If there is a change in bowel habits, a course of an antibiotic and metronidazole along with anti-spsmodic round the clock may cure your problem. If not then further study of the abdomen by a CT scan and colonoscopy may be required.