I thought I had a sudden, unexplained outburst of likes.

Obviously happy for the young lad but if you think you can explain a one month AWOL with two short lines you're mistaken. Speaking for all members here, I asked and all I asked agreed, I can tell you we expect a photo with you wearing a dunce hat and standing before a blackboard on which you wrote 50 times "I was wrong, I should have asked permission".   After receiving said photo the ballotage commission will gather and discuss your continued or discontinued presence here on the BM. As our tigger used to say 'bribes are recommended' and since the commission is a one-man commission that should not put you out too much. A dozen cans of VB would be a nice starter.

Awaiting your next move,
for the Ballotage Commission,
Uncle rubl 

A curtain twitcher, I knew it.

It's not serious, now that you've been diagnosed and are going to use the machine, if you weren't doing those things it might be quite serious indeed. Sleep apnea is very underrated by most people but it has serious implications if not treated.

I hooked a hair dryer up to a spray painters mask with a hose from the vacuum cleaner. That didn't work, so I had to fork out for the real deal.

In all honesty Rott, it caught me completely by surprise. I work shift work, and have trouble falling asleep. Staying awake is the least of my problems. I'm not particularly overweight.
So I went to the doctor to get something to help me fall asleep, and she recommended a sleep study first to see what was going on.
So basically they wire you up from head to toe with pads that go back to a computer, and it tells them everything they need to know.
So basically, to answer your questions. From my experience anyway.
You don't stay under. The body wakes itself up enough to start breathing again, and then you start the cycle all over again. No, I wasn't aware of the problem at all. The computer told the true story, otherwise I never would have known. So basically the body is continuously waking up and falling asleep over and over all night long.
I think the biggest problem is, you starve your brain of oxygen, and the heart has to work overtime to keep the cogs running. So it actually stresses the heart out. My oxygen levels were down to 80% and even lower.
I've got a monitor that I bought that shows blood oxygen and pulse and movement, and the readings I'm getting without wearing the CPAP machine are all over the place. With the machine I'm getting oxygen levels constantly in the high 90 percentage.
I can post some screenshots if you like of the difference.
Mind you, the bloody mask I have to wear to bed is almost unbearable, but it will add 10 years to my life.