First off, sorry to hear you have to deal with this. I too had the same issue as a kid. I developed what is called pseudo gynecomastia. I did not have an inflamed gland but I did develop fat around the nipple area. It ruined my self esteem as a kid. I didn't understand it at the time, nor did my parents. I stopped wanting to go to the beach or any other activity that would require taking my shirt off. It wasn't until I got interested in bodybuilding that I learned there was a term for my condition. Then I started looing at my family. I realized what happened to me was very genetic. A lot of the males on my dad's side, had "fattier" chests.
Feel around the area behind your nipple. Do you feel a lump or mass? It may be as small as a pea. If so, this is glandular material and the only way to get rid of it is to have it cut out. If you decide to do that down the road, you will want to go to a cosmetic surgeon. A general surgeon won't take the care to make your chest look good and you have a higher chance of being scarred. You may also need lypo to correct the shape.
If it's just fat and no gland or if the gland is small, there is a chance that you can get rid of it through dieting down. When dieting, we all have problem areas that are resistent to fat loss, and this will probably be a problem area for you. You will probably see other areas of your body become lean and hard, well before this area has tightened up. Dieting the fat off would be my first suggestion. See how lean you can get and there is a good chance that your pec will take on a round, pleasing shape. Also, keep in mind that the more muscle you have, the more round, and the better your pec will appear. If you don't have much pec development, it is going to be a lot harder to get the shape you want.
If you diet down, and it is still not gone. then having it cut out is the only remaining option. Once you have gyno, it does not go away on it's own. A lot of times, you hear about guys on steroids that get gyno, then use high doses of AI's like Letro and later claim that they have cured themselves. In most cases, I believe that they have just reduced the swelling of the gland, which was recently inflammed by the steroids they were using and now being staved of estrogen. In your case, it's been years. Taking a medication isn't going to change much. I'm sorry to say.
So what did I do? As I said, I was lucky. There was no mass or lump, so mine was all fat, depositied as a young teen, when my test levels were high and in flux. I went in to have lypo in my chest. Once they remove fat cells, those cells are gone for good. I am still somewhat sensitive to estrogen and make sure I use an AI while "on". Because I don't have as many fat cells in my chest, it gets lean faster than any other area of my body!
BTW, on a side note, IMO, you are still a little young for steroids, but if you decide to do them in a couple of years, be aware that steroids with a high conversion to estrogen, are probably going to cause issue for you and make this worse.
Best of luck buddy. Feel free to write in and ask questions, whenever you like.