Oh man, hangovers. They suck ass, and there isn't really anything you can do to get rid of them completly, at least nothing I've tried. People sell miracle cures, but from my experience, and those of my friends, those are totally bogus.

What I do is basically try and stay off my feet, lay in a dark cool room, and just keep drinking water. You're dehydrated, and you need to flush your system out. Sleep as much as you can, and only eat when you think you can handle it, otherwise, as others have said, you will just throw it right back up again.

Just remember, it won't last forever, and now you've learned how much alcohol is too much for you.