From here on, its nothing but frank answers. No joking in this
post.
For a guy your age to masturbate, its absolutely alright. You must
be going thru puberty now.
It is not illegal, but of course its not nice to do it in front of
someone without consent.
Try not to be distracted, it feels good yes, but dun get too
obsessed with doing it and let it spoil your life, like gambling.
You can do it, but know your limits.
Next thing, on the health side. So far no research has proven that
doing it on a regular basis might cause any ill effects, other than
what i stated in my previous paragraph. Just remember too much of a
good thing becomes a bad thing.
Cheers and good luck. 
