Ear pain when swimming

Not a Doctor, but love pretending I am.   I assume you did not have this prob before.  Maybe stating the obvious, but you might wanna try earplugs.  That helped me a lot, just alleviating the discomfort of water on the ear and the "pain" of trying to shake it out - (that usually gave me a headache). 

I sometimes have some sinus congestion after swimming, just chalk it up to the chemicals. 

This was very helpful, huh?????  Now I know why I have no patients (or patience for that matter).

I have somewhat the same problem - Swimmer's Ear.  Water gets in my ear and won't drain out.  Don't know that you have swimmer's ear, but you may have had water trapped  in your ear all along and it never really gave you a problem; until your flights may have caused some inflamation, and with the water in there it caused swelling, or even a minor infection (not to worry - pretty unlikely - probably just some swelling due to the irratation)

IMHO, using Swim Ear will probably eliveate the problem.  I can't stand ear plugs, which is what my Dr. recommended, but he said the better alternative is Swim Ear anyway.  They are drops you can buy at any drug store or grocery store OTC.  They work great!!!! :-)  Just a few drops in each ear immediately after getting out of the pool, and I have not had a problem in years.