There's no itunes app on my iphone?

It's an iphone 4 running ios 6 and its not jailbreaked (never was) and there's no longer itunes on it. This isn't normal please help

First, try swiping till you get to your search screen and type in itunes. You want to make sure your not just missing it. If its not showing my guess would be that someone placed a restriction on it. Go into settings under general. Find the Restrictions and click it. It will ask for a password if they are enabled. If you don't know the password find out who does.