hit the door panel right next to the speaker with your fist. Hit it hard, trust me. I can't take credit for this though, learned it from another site. Saved me a repair bill though, so at least try it prior to taking it to the shop. Worked for me.
my driver side window wasn't working for a long time (a year or so) using the switch on the panel. one day i used the function on my key to unlock and open windows by pressing and holding down the unlock button, and my window rolled down! since then, it works fine.
maybe it just needed a break.