I'm 38 year old female. high bmi. i have severe breast pain mid cycle. lower back pain, headaches. meds. glucophage (metformin).

Hormonal : With the limited information you provided it sounds like you have premenstrual syndrome. Certain foods and lifestyle can make the symptoms worse but there are things that might help. Avoid caffeine and chocolate to help breast pain. Low carb diet and eating small, frequent meals with adequate protein and fat to control blood sugar will help headaches. Weight loss is important.