My ear really hurts and I really need to know what it is

Since like last year I’ve been having this thing where anytime i go to a public pool, my ear starts to really hurt the next day for a few days. I even feel like there’s pimples in it when I stuck my finger there (which btw hurts a lot).

I thought it might be swimmers ear, but my problem does go away on its own after a few days and then comes back after I got a public pool again (and I do swimming as a sport).

And it’s always the same ear btw (the right one)

If a medical professional could answer me that would be great thank you!

I’m 14 years old with no other medical problems.

Idk if it’s needed but I weigh around 55 kg (120lb I think) and I’m 171 (5’7)