Dear nekoshima,
you have big plans, of course you are nervous!
I know how it feels to have a knot in your stomach. I had that in the past, to the point where I wondered if I had developed some serious medical condition. x_X I think at that point the anxiety isn’t useful anymore.
One of the things that helped me was autogenic training. It’s a way to relax your body and (at least for me) it has the effect of giving my brain a break, too. Here is an example video: https://www.youtube.com/watch?v=74aXSxyi8oo . Lay down comfortably, put a warm blanket over you and try it, if you want. 🙂