In your case, if you are unhappy about the shape and contour of your chest, plastic surgery can help.
I don't believe that diet and exercise alone will eliminate the female like contour of your chest. It looks like you are currently at a decent weight, so the "is it fat or gland" question really doesn't matter.
If you are really unhappy with your chest, consult with an experienced plastic surgeon. He or she can detail the results you could expect from surgery.