Ok, you might just have to really try and block your sickness out. You may do a lot better than you think. Something similiar happened to me this semester, except it was two midterms on the same day (biochem was at 8am, and Organic at 5pm!) The worst thing about it was, I tossed and turned all night long. Finally, I gave up and decided to just stay up. I literally was so sick, and so ridiculously tired I thought my grades were ruined. The first test came at 8am, then I had to stay up until 5pm for the second test. I sat in a private room in the library drinking a couple red bulls. I really thought I was screwed. After the second test, I waited in fear. I kept reminding all my friends that I probably was so out of it I spelled my own name wrong......Well to my huge surprise, I got a perfect score on both of them!! The funny thing was I had already emailed both my profs to explain how I had been sick and did not sleep for a day and a half. The probably thought I was crazy. Who knows, maybe I am🙂
Anyways, the point of the story is to not worry too much. Sometimes you can be so out of it that you don't over analyze details on the tests. Thus, you just start writing down what you know. Good luck.