Years ago, someone asked me to help with her bag. I declined and someone else immediately offered to help. I thought nothing of it, but it must have bothered my seatmate. He must have spent the five hour flight angry at me because once we landed, he launched into a tirade that he probably rehearsed throughout the flight. I let him speak while everyone nearby watched. Once he finished, I gently lifted my shirt to show him the bandages from the surgery I had about 2 weeks prior.

"I can't really lift my arms above my shoulders right now," I said. "That's why I put my only carry-on bag under the seat."

I actually felt badly for him because he probably spent the entire flight being angry at me. Not all physical restrictions are apparent solely based on appearance.