Thanks for query,
First of all masturbation
is a common practice in your age group.
It will not lose any essential elements from your body to make you weak.
Your symptoms are more related to depression
rather then weakness.
Take healthy nourishing vitamin rich food.Avoid junk food.
Don't go for masturbation excessively.
to divert your mind when you have desire of it.
Remember you have no disease & you need not to take medicine.