Prepared to take finals?

I am honestly really nervous to take finals.  You can either do really good on your finals and it won't raise your grade much higher but will atleast keep it the same, or you could bomb your final and have your grade drop about 4 or 5 percent!  Finals scare me because its my last chance to get a good grade in the class.  As of right now I don't think I'm completely prepared for finals!