I used to get very nervous on driving tests too; so did my Mum. She passed by taking valium before the test, but I didn't fancy that and just kept at it. Eventually passed on my eighth try - in an area I'd never even been driven around before.

I didn't so much get over the nerves as learn to drive even when nervous, but whatever the reason I'm very glad I got it in the end. I see no reason why you shouldn't too.