What to do about pain in my lower right side?

Depends : You do not tell if acute or chronic & if is related to any injury. Assuming is chronic you first need to be diagnosed. Therapies are rationally determined by the cause. Up to 30% of people with chronic low back pain have this from injury to pelvic sacroiliac joint. Pain usually in low back on one side with radiation pain to groin or posterior thigh. For diagnosis see an osteopath.