If when you say your “screen broke”, you actually mean “you can’t see anytihng on it”, I’m not surprised you can’t find you music after unplugging from your computer. Did you really expect to? Without knowing what main menu option is on the screen at the time, there’s no way to blindly navigate to it. 
If this is not what you meant, maybe if you give some more details we can help you. Otherwise, it sounds like time to buy a new player.
