Is it causing you physichal discomfort? I was pretty big (D+) as a teen, but when I got pregnant I lost weight, and now I'm a C...which suits me perfectly.

You should be careful with getting any surgery done on your breasts while youm are still so young...in a possible future pregnancy you could get problems, not to mention breastfeeding...which could be completely impossible.

But, if this is a huge problem for you, you personally, and not your family, get it done. But remember, it's your body, you have the final say, and you should never go through with something unless you are absolutely sure you want it.