Yang-Yang's awakening subplot (SPOILER)?

After two viewings I still didn't at all "get" Yang-Yang's subplot with the upskirt view, the audio-visual room silhouette, the clouds and lightning and thunder, and the swimming pool ...and his ending comment that he now "feels old". Even after it was explicitly explained to me, I still had trouble buying it.

I eventually realized why: I just don't expect children of that age oto ever have even minor pre-pubescent pangs.

Then a bit of the commentary jumped out at me-- Edward Yang said he had originally written the character to be about ten years old, but then because one actor was so good he'd cast it a couple years younger. It was indeed true that the action I was seeing and the actor I was seeing didn't quite match.

Did anybody else have trouble with this???