If studying more will just make you nervous for the test, then do not study more. Really, just hide the books and relax.
BUT: if you feel calm while studying, and nervous when you books are away from you, like you're missing something, then go ahead and study, but gently. Don't do any more cramming. I fit into this category, so I had my notebook with me on the train going in to take the test. Did I learn a whole bunch more? Gain ten points? Probably not. Did I feel better knowing that I had it with me? Yup. 🙂 Then again, I was the kid who always had to take my notes with me to a test, even if I didn't look at them that day.