Pain on the Side of Breast(and at the Juncture of Armpit)

With a normal mammogram and close follow up by your physician, I believe you can be reassured about their recommendations for close observation.

Pain by the armpit at three years post surgey can be many different things, including but not limited to scar tissue, infection, irritation, to name a few.  Close vigilance of problems is key .

Breast augmentation is surgery and any surgery may result in some degree of discomfort or pain afterwards. When the implants are placed under the muscle the procedure is often more painful than if the implants are under the breast. Usually this will resolve over the course of several weeks. Your plastic surgeon should be able to assess if your situation is due to a condition such as capsular contraction, where abnormal scar tissue develops, and whether any intervention is indicated.