Two things: you are too young to do steroids, and you are too young to have done steroids.
Epistane is not prohormone, but a designer steroid. Designer steroids and ph's cause a decrease in your own bodys testosterone production, and since you took them at such a young age, put you at risk of having major endocrine system issues later in life, sinxe this system is still developing. This means that there is a possibility you will need to be on hormome therapy for the rest of your life, starting anywhere from your late twenties to early thirties.
I would highly suggest (and I would imagine other AM members as well) that you not use this product, or any others like it until you are at least 21, when your endocrine system has become fully developped. You have the potential to make a lot of gains on your own if you learn about proper nutrition and training techniques.
Pm me and I will send you some info on how to eat/train for size. But do NOT take any other ph/ds for at least another 5 years...and just hope that you didnt do much long term damage to your body.