Dont worry about it, I still get nervous, we all do from time to time, that is why we are human beings and not robots, quite frankly I would be worried if you werent nervous as over confidence is a far worse mistress than being overly nervous. Remember you have been on this earth, stood on your feet for thousands of hours, and have only sliped the surly bonds of earth for 30 hours, it will take some time to get used to, just stay as you are and it will come. Promise!!!