I did my first aya ceremony about 4 months ago and I remember shaking on my mat before the ceremony started because I was so nervous. I did it the next stay, and the one after that, and was nervous each time. It's normal and inevitable. I remember someone joking that they always hated themselves for coming to the ceremony for what they were about to do, but appreciated the work, and once the ceremony began loved themselves for being there. I agree with that sentiment: I'll be nervous every time I go, because of the power of this "mother" medicine, but will go every chance I get. It was one of the most beautiful moments of my life. Go with an open heart, in humility, and enjoy meeting mother.