+1

Was standing next to an obvious underager who was outraged when the bartender asked her for proof of age. Since I was mellow enough to be willing to share my much greater experience, I did tell her that if she was over-age, she be gratified, not outraged!

To the OP - you would be considered too young to sit in the emergency exit of a UK registered aircraft. It's not just about physical capacity, it's also about willingness/ability to take responsibility for getting that door open in the event of an emergency. While you, by sitting there, clearly showed you were willing to take responsibility for the lives of the people around you, not all young people of your age would have the maturity to understand and accept that's what they were doing by sitting in that seat.

Personally, I'd ban anyone from the emergency row who tried to stow anything at their feet, instead of in the overhead, as its clear they don't understand the importance of that row. But since I've read some very nasty accident reports where people were overcome by smoke before they got off the plane, then I do know I don't want anyone uninformed or unable in that seat. Yes, it's selfish, but I think I have a right to be