My Nikon camera won't turn on?

So I was taking pictures all day at a swim meet today, and I came home and charged it. Then I plugged it in my computer to upload the pictures on my computer, but I fell asleep(haha) and left it plugged on my computer.
Now it won't turn on. And I tried charging the battery(you have to take it out and plug it in individually) but it still won't turn on!
I'm freaking out! I don't know what to do.
Can anyone tell me what's going on? Or what to do?
I think it might have been that I left it plugged for like an hour and a half on the computer.

Thanks in advance.

Cheers!

Added (1). I think it's a DX. I mean, that's what it says on it.
I'll try the reset button.

Maybe its not the batteries it could be the camera itself

Which camera model? First remove your memory card and battery. Charge the battery overnight and try powering on the camera again. Note some Nikon's have a reset button, the manual will tell you if your camera has one and how to use it.