I'm sorry you had to go through that Mari
Those things are miserable! It is always frigid. The ones I have gone through have always had a "lights out" policy, which I found to be intolerable at the time. I hope you don't have a bunch of crap stuck in your hair, and you get some good sleep in today and/or tomorrow.

I'm sure they wanted you to sleep in because they were greedy for more data. I hope that the results will help your doctor help you get more quality sleep