Psp wont turn on!?

Ok here's the deal: i wasn't home and my sister was playing "Burnout" (which is a really good game btw) and from what i understand she was playing with the charger plugged in and the psp turned off.She said that she left it ther to charge for a while. she came back to play it again and it wouldn't turn on and the yellow light wouldn't even turn on, in fact none of the lights will turn on. No sound, video, or power it just wont turn on!I figured it was the battery so i bought a new one and it wouldn't turn on so i hooked it up to charge and it wouldn't turn on either. So i have no idea what to do. My PSP wont turn on, it wont charge and none of the lights even turn on!So if any of you have any ideas of what to do to fix it please answer!I would really like to hear from a person that had the same problem or from someone that knows how to fix it!thanks!:)