what causes a hangover and how do you cure it?

I've been drinking for like the past 3-4 days nonstop and I really don't feel well!!!!! I feel nauseated, queasy, tired, half-drunk and I really just wanna lay down but I can't because I'm at school right now. How do you cure alcoholism and how do I get rid of this awful hangover?

drink a glass of water. take some tylonol or dayquil. drink some coffee. go to mcdonalds, eat something greasy and fatty. hangovers are caused because alcohol dehydrates you body. since it dehydrates your brain as well, your brain shrinks a little due to the lack of fluid, and the thin membrane that connects your brain to your skull starts to tear away. hence a hangover is like no other headache. this is also why it kills brain cells. just do what i told you and you'll be fine though.