your condition is terrmed Gynecomastia
which is enlargement of breasts in a male. It can be painful or painless and the reasons for developing range from hormonal
imbalance, medications, idiopathic( no known cause), etc..
if there is any endocrinal problem, it can be treated by medications/surgery. however if it is idiopathic and is bothering you cosmetically it has to be treated by surgery in which usally the scar will not be visible.