I guess with most cases for BPs I would agree since they seem more keen on hiding than defense. I would still put money on one that isn't handled often being more likely to bite than one that is. Probably depends on the specific ball as well.
I do agree that she thought you were bringing her food or was sleeping is a likely reason. You probably both just scared the crap out of eachother.
I don't think that matters, as much as the actual personality of the individual snake. I would bet I could not handle my bee for awhile and she would still be the sweetest thing around. I can handle my butter all the time, and she still has her moods.
If nothing ever changed, there would be no butterflies.