It's not uncommon to feel guilty about masterbating, though it's kind of a waste of your emotional energy because there is nothing wrong with masturbation. If you were referring to masturbating that much when you asked if "that" is normal (I couldn't tell if you were asking if feeling guilty is normal or if masturbating is normal), yep, it's pretty normal. Maybe your pace is a little more than some people, but your teens is when you're most run by your hormones so it's probably also a little less than some people in your age bracket. If you find that it interferes with your life, such that you don't do other things that you would like or benefit from because you want to rush home and masturbate, then, see what you can do to pace it. (Just like being on the computer a lot or watching too much TV, anything done in excess can crowd out things that do good for you in other ways.) But even masturbating every day or every other day doesn't usually take that much time. Don't worry.
Nothing to feel guilty about other than maybe having too much free time. Read a book, expand your mind. :>))