The main cure is to stop swimming. Nope. Not there yet, if ever. There are over the counter fixes that I'm going to try first and more than one place suggested a hair dryer blast (on cool) into the ear after swimming. This I can do easily.
And, yesterday, I finally remembered Tylenol. That helped tremendously. I'll pop into the drug store after my swim (and ear hair drying) this morning.
The baseball game is at 10 so plenty of day available after.