I read an interview with her some time ago, and apparently she was on some kind of medication for allergies. She just happened to be in the studio to watch, because a school friend's father worked there, so they could get in.
I this advertisement became famous in the USA some months ago (last summer, I think). I'm from Spain, and I haven't watched it in TV. I first heard from it about two months ago from a colleague at work, but he said to me that the girl was acting that way because of having smoke maria just before filming her ;)