I reckon masturbating is fine. If you're not in a relationship, your body still has its needs for sexual expression, so go for it I say! How much time is it wasting? If the alternative is spending hours drooling over porn, to me the answer is simple.
To me this doesn't sound like it's the time that's your concern, but maybe you've picked up some unhealthy ideas about sexuality. I don't know where you live but if your culture has conservative ideas about sex, you may be suffering guilt.
Masturbation is a perfectly healthy release for sexual expression. Don't let anyone tell you otherwise!
Joy to you