Anyways, OP
I started programming in high school at 15 on my TI 83 calculator (lol).
After that, my first language was Java. (Don't go there)
To learn the basics of programming, I would actually rather recommend programming on a calculator like the one I did if you've got one laying around. Here's a really basic tutorial:
http://www.ticalc.org/programming/columns/83plus-bas/cherny/#beginning
Otherwise, I'd recommend Python. I personally don't like python, but you've got to learn somewhere, and it's a really easy language to understand. If you care about why I don't like it, ask, but it's not too important if you've never programmed and don't plan on doing anything huge.
This won't teach you any of the Computer Science abstract awesomeness that we all love, but that's okay. Learning to program is more important for you now anyways.
After you learn languages like this, I would recommend Java or C++. You would program in these languages like you would in the calculator language or python, only they introduce object orientation (OO), which is a very big idea in modern programming.
Of course, if you're (really) good at math for your age, Lisp and Haskell are good languages. They're very different from all of the other languages that I've mentioned in that you program functionally. Everyone here will recommend them, and I almost did as well, but in hindsight, if I'd started programming in Lisp or Haskell back in high school, I would have probably stopped programming.
Good luck OP.