The mouth, the nose, and pillows

What is it about pillows that causes different reactions in the nose and mouth depending on how high or low they are? (I recently got a new mattress.) If the pillows are too low, you can wake up suddenly, feeling like you have to go vomit. If they are too high you can wake up with a stuffed feeling in the nasal passages. I don’t have that, but I do get an accumulatinon of this awful matter in my mouth that gives me a dry, thirsty feeling. (I called it “bee glue” when I would get it as a kid, but now of course I have more colorful names for it.)
Anyone of the Teeming Millions have better information on pillows’ effect on breathing and the mouth?

That could be acid reflux. There are lots of ways to deal with it, none of them certain fixes and most of them rather annoying. For instance, I not only take a prescription medication, but I also take 2 antacids right before bed, I sleep on a bed wedge, and I don’t eat anything for several hours before bed. I’ve restricted almost all caffeine and spicy foods from my diet, as well.

That’s sinus congestion, also addressable. In my experience, more easily so and with much better success. Those adhesive strips may work if you don’t want to take the obvious step of trying a decongestant.