Sup brotha.
I'm new to this as well and suffer from the anxiety of falling alseep too. It seemed to starta bout 2 months ago, but once your body knows that there are issues when sleeping, I think your brain subconciously prepares you to do something about it. You are, so that's good. you may be experiencing the anxiety most jsut as you are falling asleep. That's when mine hits me. I start to cross over to sleep and then wake up gasping and freaking out. Then I stress out, sit up, try and sleep sitting, toss and turn, and end up drained all day.
I just got my BIPAP machine, and it's making a world of difference. I had to go through 2 sleep studies because ironically i couldnt sleep during the sleep study. The second one was a titration study and they figeted with the dials like a HAM radio until I fell asleep. I've been on mine about a week. I am not symtom free but i think my brain is getting used to the device at night now. I wake up rested for the most part.
Make sure you sleep during your study. That's the most important thing. It is a little odd with all the wires, but if you are tired enough going in, you'd sleep through a parade. Get a good work out in on the day of the sleep study so you rest. It will take the edge off.
GL and keep us postd.