Thanks again everyone. To answer quickly, I am not on any medication, have no known allergies, sinus infections, or any stuffed nose/snoring problems. I'm in good shape, I sleep like a baby. My 75 year old mom still does not wear glasses and, fortunately, I got that gene from her as I am not yet wearing glasses. CO2 retention is possible since I am good on breathing very slow while diving. On a 45 minute dive at 60 feet, I'll come up with half a tank of air. I've done the nitrox class just for the heck of it but other than the two nitrox dives I did as part of the class, I have never dove with nitrox so I can't blame nitrox. I will try the pseudoephedrine suggestion.
Cheers,
Michael