My iPhone 4S not playing music or making any sound when someone texts me?

When someone rings me it does go off but when someone texts me it won't. Nore will play music. My phone is not on silent. I've turned it off and on several times. When I put my headphones In it will play music when I take my headphones out and play it again it won't make any sound. Any suggestions?

Added (1). @tyric I've tried turning the volume up. Still won't work.

Added (2). @whatcity225. Nah hasn't Been moved. It's on loud which it should be. Got told to reset my phone but if I do would everything go? Including pics, vids, contact ect?

Turn the volume up

There's a small slider button on the left side to mute the sound. Has that been moved?

This is an Apple conspiracy! I've had this happen. They want you to buy the Bs IPhone 5. Time for Samsung.