Re: Should I not?
This is a tough one. Determining what is 'Wrong' is a very personal matter, and I doubt anyone here can (or frankly should) be offering you counsel on personal morality.
I suppose the best thing to do is either ask them directly and have a conversation about your feelings and urges, see what they say. They actually might be more understanding than you think, even if they have a problem with masturbation. Or, you can reflect on your upbringing, your values, what you've been taught, and arrive at your own conclusion based on this.
The most important thing isn't so much if it's ok to masturbate or not, it's finding out how your family (and your religion) feel about the normal sexual urges everyone has. It sounds like it might be important to you to get thier ideas not so much on masturbation, but more importantly, human sexuality. Masturbation is, afterall, just the 'result' of the universal sexuality we all have coursing thru our veins. Feeling 'shame' over masturbating or touching yourself isn't as important as coming to terms with natural biological sexuality. There's no shame in that. Perhaps your folks can help you come up with different ways of reacting to those natural urges that don't violate some of your religious beliefs. But also don't lead you to feel shame and guilt over something that's essentially normal.