You run the risk of stopping your growth. You're not as big as you're going to get - unless you juice - then you are. You should - if you don't juice - get alot thicker in the coming years. I stopped getting taller at about 16 but I got wider for a few years and then thicker for a few years. You want to let your body grow awhile longer.

At your age your testosterone levels are very high. Use it to your advantage. The earlier you start de-sensitizing your body to steroids the less you'll get from them in the long run.

Burning up your bodies ability to gain from steroids at your age is like going on "Who Wants to be a Millionaire" and using up your life lines on the first 3 questions even though you know the answers.