Ok, so i have an iPod Nano 4GB the normal one that everyone seems to have. I'm 16 and was at college flicking through my playlist, pressing next while it was till on play, so it was jumping from one song to the next etc. then i get to a song i want to listen to but it isn't playing yet it shows the blue play button in the top left hand corner still. the timer on the song isn't moving past 0:00 and my earphones definatly work. it's playing but the timer isn't moving and i can't hear it?

I haven't dropped it recently or had it bang against anything. Help!