You are going through what is a normal physiological process--puberty--in which as high as 70% of men will develop some degree of gynecomastia, 95% of which go away in a 3 year period. Those are numbers worth remembering--this is a very common thing, but most young men don't talk to one another about it (or at least they didn't when it happened to me at age 13...I was sure I had cancer and was going to die!) The internet allows for a raised degree of awareness, but things like treating with Tamoxifen, and so on, are not good options during the time of hormonal sensitivity anyway. You want your body to do what it's supposed to do, and unfortunately if you have gynecomastia when that's all over, you may need surgery some day. But if it's been a year, you have at least 2 more years before surgery should be considered. And I don't think medication should ever be used, except in very limited situations.
Good luck,
Rick Silverman