I have a sharp piercing pain in my right breast and partial of the right side if my chest what could this be?

"Mastodynia": Sorting out different causes of breast pain starts with determining if the pain is coming from the breast tissue or the chest wall. Favoring the former includes variation w/menstrual cycle; favoring the latter is relation to activity and post-menopausal state. I recommend that you see your gyne or primary care dr. To help sort thru this. Good luck.