How do you get out of hibernation?

If you can't get out of hibernate, you (most likely) have a serious problem. Obviously you tried to turn it back on with the power button, so that can't be your problem.

Try the Hard Drive in a different computer (the one you asked this question on) and see if it boots up. If not, take it to someone you trust to fix it, whether it be a friend or a company. Friends are always much better.

Next time, don't put bears in the tag. That would be considered near spamming.