I'm nervous about my final accounting exam, GD

I been doing great in class all year round with straight A's on everything, but after dealing with the flu and having little energy to do much about it, most of my preparation for the exam has been sleeping extra and being drowsy from cough suppressants. Also I had to take the makeup exam I missed last week after the final so I will be taking basically a four hour accounting exam. I really am nervous for it like what if I do so badly I don't get the A in class? I'll be so sad after all that hard work I put into my course :( Now I have the option of staying up all night long and do like a bajillion questions but I know that won't work and I'll be miserable tomorrow and probably make a lot of mistakes if I have no sleep so I gotta go to bed early and wake up early to study a tiny bit and just bite the bullet. Ugh final exams are toxic, I been good all year why do I have to prove it again? In other news, A in management from both the final and final grade, so at least one good thing came out of my struggles.