I have mild gynecomastia, and have, decrease vitamin d3 from 1 month I get pain in left chest, headache, neck pain, ribcage pain back pain. I am taking vitamin d3 supplements. Sometimes I get electrical shock in left chest. May I know the reason. I hve done 2d echo in nov there was no problem I have done ultrasound in that it shows mild gynecomastia. And have done blood test. I had low d3. But I am sacred because of chest pain in left side, and headache, arm pain and neck pain. May I know the reason for this pain. I hve this symptoms since 2 week.