I struggle with equalizing my ears a lot, and almost always end up will an ear full of water for a few days. As a child I had a lot of ear infections and ended up having tubes put in both ears. My ENT isn’t a diver but believes the tubes slightly stretched my ear canals which is why I end up always having flooded ears. He asked if mine were plastic or metal which I couldn’t remember as they were when I was really young. He said is they were the metal version it may has stretched my canal a tad more than normal. I also have typically longer descents since I struggle with equalizing. I’ll have to go up and down a few times before I can actually make it down to the group.
Is water flooding the ear channel (hence the water reaches the timpanic membrane from outside, but does net enter in medium ear cavity) or is the water going through the Eustachian tube, flooding the medium ear?
The first case is quite normal, I usually flood both ears as I dive, leaving surface, and I empty them after emerging.
It should cause no problem.
Instead if water goes inside medium ear it can easily cause irritation, infections and temporary hearing loss.
Albeit flooding medium ear is done by purpose by some deep free divers, I would recommend to avoid it.
It can also cause vertigo and loss of orientation...
However it is not clear how this is happening to you. It is not easy for water to penetrate inside your nose and reach the medium ear through the Eustachian tube.
Are you sure that your timpanic membrane is perfectly waterproof? If there is a tiny hole, consequence of your jouvenile othitis, this can allow water to flow in.
In this case you need some surgery (timpanoplastic).