The Chassidishe Gatesheader -“I never go to a mikveh since I have extremely sensitive ears (had tens of ear infections when I was young) and was instructed by my ENT docs then, never to allow my ears to go underwater at all.”
I’d ask a Shaila if I were you. It might be a Chiyuv Erev Yom Kippur and possibly erev yom tov. They have ear plugs that can keep water out or putting in mineral oil. This might not be considered a Chatziza. You can also use alcohol, mineral oil, or vinegar afterwards to remove water that got in.
Btw, how do you shower? Doesn’t water get in?