The only effects of masturbating too much are potential irritation/chafing from handling yourself too roughly, and potential difficulty maintaining relationships and/or attending to responsibilities if masturbation becomes an addiction. Anything you've heard about masturbation stunting your growth, causing blindness, hair loss, hair growth, etc. is a myth.
However, after more than a century of generally dubious and sometimes lunatic penis enlargement attempts, there's still not much you can do. Sure, there are lots and lots of supposed options out there -- penis pills, creams, brutal stretching exercises, horrific-looking devices, and penis surgery. Almost none of it works. The few approaches that can work often have modest benefits and serious side effects. How serious? In some cases, erectile dysfunction-serious.