Yeh honestly mate at that weight u still have a lot more Potenial naturally with a strict diet plan and a good training/recovery reagime. By using steriods (hardcore stuff as u say) at your age you are very likely to damage you're endo system. Your still developing right now so why risk it. You don't need the alt steriods at all like said above. My advice is to work out a really good diet/training program that suits your goals, build a good base naturally off that and then if you still want to go down the path of steriods then come back when ur 25...

Goodluck