I can't access my iTunes Store app on my iPhone 5?

Everytime I tap the button to access the shop it just pops straight back to my wallpaper and out of the app without even sayin can't access store.
What could be wrong?
What can I do?
Also people are not receiving my txt messages yet I'm receiving all of theirs and my phone is telling me mine have been delivered.
Any ideas what I can do?

I suspect you updated your iphone to iOS7 and that's what went wrong check below if i'm right and search for your issue and you will get corresponding solution

http://wizdroid.blogspot.com/2013/11/iOS-7-Problems.html
http://wizdroid.blogspot.com/2013/11/ios-7-problems-p2.html
http://wizdroid.blogspot.com/2013/12/ios-7-problems-final.html