You ask about drinking and age... but you have to consider not the amount your are drinking as well but the mental aspect of it.
How mature are you? That wasn't meant in a mean way... but your thought process also affects you as you grow.
I was growing up in different business many being bars etc and seeing people drinking all the time wasn't nice.
You are young.. and if you are doing it to fit in... hide from something.. think it is clever... be one of the boys... not facing what your real problems are then there is a great possibility that you will turn into one.
If you have a problem... depressed .. fight the problem not fill it with a poison... your better than that...
Don't go down a route that you are going to regret later... if you are depressed then turn that around.. go to the gym and work on yourself there. Don't give any excuses... you can spend plenty of time thinking about your life.. your prospects there while you train out and do something good for your body... you may even find that turning those negative thoughts to positive thoughts will change your life for the better... NOT the bottle!!!