I Have Pain In My Armpit, The Same Place Every

I have pain in my armpit, the same place every month and it hurts for 2-3 weeks before my period giving me relief only when my period starts. My breasts are also unbearably sore. I saw my doctor about this, had a mammogram (this year too) and she gave me antibiotics and told me to skip shaving and using deodorant. I almost can't take it anymore. Can you please tell me if I can do anything to ease it?