WELCOME! to the forum.!
You might talk to your doc about this and ask about getting something for your allergies, hang in there for more suggestions and good luck to you with your CPAP therapy.
Turns out my issue may be a TMJ issue (found this out after further research). I don't think it's the CPAP machine causing the issues. I think it's the chin strap. Thoughts anyone??
Btw: I have worn a mouthguard for years. I clench, not grind my teeth.
I don't get ear pain, but I did have TMJ pain after starting CPAP. This gradually went away over the course of a few weeks. I think it was my body adjusting to the new sensations.
I have TMJ too. With an AirFit P10 (strap at top of head and at base of skull) nothing is really pulling on my jaw, so I'm not aware of any worsening from the CPAP. However, I spend my whole day consciously slackening my jaw, and being aware of loosening the jaw muscle. I sometimes wear my 2nd bite guard (I wear two, non releated, but they happen to be upper and lower, so I can wear both every night) during the day, to keep the jaws apart without requiring the focussed attention.
At the beginning of this summer, I had a 6+ week long headache, and could barely open one eye at bright lights. I finally traced the problem to the muscles of the face, not the vision --- and THAT problem was eventually fixed by an antibiotic for an otherwise non-symptomatic sinus infection. The muscle strain --- at my eye, but connected to the TMJ issues -- disappeared immediately after the first antibiotic dose took hold. The only moral I can see is: the sinuses and the TMJ and the whole face are connected. So suspect all of the parts!
Which isn't immediately helpful to you, but might make you think of something. Could the CPAP be giving you sinus problems??