Thanks for query,
First of all don't worry about your loss.You have loss nothing.
is common in your age group.How many times in a day or week is not a protocol but when you desire for it you should go for it.
Sex is in our mind.
So just divert your mind by doing meditation
or busy yourself when you have desire for it.
You should remain more with public or with persons ,friends will decrease the chances of masturbation.