Before he became mature after he swam threw the tunnel. He was a normal childish 11 year old boy. For example: "began splashing & kicking in the water like a dog" only little kids would do something like that. Another example is how he said "i want some swimming goggles."
He was just a normal childish 11 year old. Like when he "balled his hands up & cried" just because the boys left. There is no reason why he should cry