I've headed out of exams and into thesis territory - and let me tell you, the nerves only get worse!
On a lighter and less depressing note, basically my usual philosophy was that if I studied as much as I could and gave it my best effort, then I had nothing to worry about - basically, that whatever would happen would happen, and I'd done everything in my power and that it was up to the fates. Clears up the nerves something wonderful.
Alternatively, go do something distracting like...playing video games!!! =D