Can drinking too much green tea be a bad thing?

I have a sore throat with a stuffy nose but I want to get better by tomorrow so I can go to my friend's house to watch the Superbowl (:D). I heard that drinking tea is good for you when you are sick. So if I had like 4 or 5 cups of green tea today would that be bad? I want to get better as fast as possible :)