Oh, I meant I believe duderino when he says he thinks some bubbly people who laugh about 'nothing' are actually shy/nervous, and that tickling occurs to him. But yeah, I don't agree, just to make that clear. Even if someone is 'bubbly' out of nervousness, I would never called that shyness. And if the OP says she approached him and came across as bubbly, I don't suspect that he took her for a shy type for one second. And I don't think that correlates to ticklishness anyway.
Well, the Op's version is just that, his perspective. I'm sure the person in question might have another, and so would a third person who got all the facts.