Dani, I have flown 6 times since my treatment in April and many times before I was diagnosed and never experienced any adverse effects. I recently returned from a 10 hr transatlantic flight during which we were seated directly behind the wing engines and the noise was bad, even with headphones on. I did have an increase in dizziness and a second tinnitus sound that developed after that flight. It took about 3 weeks for it to return to normal. Funny this didn't happen on the flight to our vacation destination, but we were seated in the center seats of the aircraft well away from the engines on that flight.
That was a long-winded way of saying protect your ears and don't sit near the engines as an added precaution. Also, ears popping with a change in altitude does not happen to everyone, so don't take it as a sign that you will have pain with flying.