The music app on my Iphone 4S is stuck.

The music app on my Iphone 4S is stuck. It keeps playing that same song over and over. It won't progress to the next song on the playlist on its own, I have to use the next button to move it to the next song manually. The shuffle doesn't work either. I was going to delete it and reinstall it, but I can't even get an x to appear in the corner to delete and reinstall it (perhaps because it came preinstalled on the phone). Anybody have this same problem, or a solution?