I can't download apps on my iphone 5 on ios 7?

My iphone 5 is running ios 7 but it won't let me download apps, i can use my moms account and it works fine but when I try to login to my account it says it can't connect to the iTunes Store but I message and iCloud are fine is anyone else having this issue and how do I fix it? I can't use iTunes Radio or anything

What does the error say EXACTLY? What is it doing EXACTLY?