I have apnea, and so do a number of my friends. Rather than debate normal/abby, lets just say its VERY unhealthy. That said I have to say a night in a sleep lab is one of the worst experiences I have ever had. I simply cannot sleep on my back. As soon as I drop off my airway just closes, no maybe etc., air no longer goes in or out my nose. I breath through my mouth or not at all.
The sleep study of course requires you to lay on your back, so I got to enjoy a couple dozen passes of falling asleep, followed by immediately waking starved for air with my heart pounding. The next step in torture was Cpap, basically a mask goes over your nose and air is pumped in to keep "constant positive air pressure" in the nose throat air path. Part of this is a chin strap so you can't breath through your mouth. This did NOT go well.
Later I found something less than half the people who try Cpap ever learn to tolerate it. One of my friends just loves his. The result for me was that I became so paranoid about breathing, that sleep was very difficult for months afterward, and for more than I year I was VERY sensitive to the slightest breeze, even a fan blowing in my face. Trust me, thinking about whether or not you are breathing "well, or correctly" makes for excellent panic attacks, and makes the basis of some effective methods of torture.
The reason I mention it here, is that you may want to think twice before entering a sleep study, or even getting yourself on to some list of people with sleep disorders (ie the free booklet). This is an evolving medical area, and the best doctors I know of do things very differently now compared to maybe 5 years ago (surgery is seen as much less effective for example). Do not just ignore the problem, but this is NOT IMHO a good area to just do what the doctor tells you. You must learn about the issues and your personal condition at least enough to make informed questions. One last BIG point is that if you are a night owl like me, be aware the sleep study expects you to be normal, ie falling asleep around 10 PM. If you don't go to sleep until 3AM, expect a LOT of trouble, up to a total waste of time for all concerned.