my estimated age is quickly decreasing

On the flight home from Chicago I had a great seat, aisle with an empty chair beside me.  The conversation that followed went something like this:

Flight Attendant: "Are you travelling alone?"

Me: "yes"

F.A.: "Would you like to sit in the exit row"

Me: "sure" (you usually get more leg room in the exit row)

F.A.:"Wait, how old are you?"

Me:"25"

F.A.:"Okay, great.  Follow me."

At which point I followed the flight attendant to the exit row.  And this other guy joined us on the exit row, and he took the aisle, so I had the middle seat.  And the seat was excrutiatingly uncomfortable.  So much so that I had to lean forward during the whole 4 hour flight.

While sitting in the exit row, I grabbed the little booklet to see how old you had to be to sit in the exit row.  15.  Not 18, or 21 or anything even remotely close to my age.  The flight attendant lady seriously thought I was quite possibly younger than 15.  Yikes. I was dressed well, minding my own business.  I was not acting like a teenager or a pre-teen.  Yet, even at my best, I look younger than 15.  Awesome.