Glad to hear you managed to stay in the bus. Isn't that something like claustrophobia, like the fear of enclosed spaces? I also have that a bit, I always want to be sure to get out of one place if I need, that why on concerts, I'm never in the front rows, but always behind, so I can leave immediately when I think I feel faint or such.

I also pretty feel uncomfortable when watching a movie like The Descent, or lately Frontière(s), when they crawl to a very small tunnel and someone's following them.