Good grief. Sounds like a lot of politics to me.
It sounds to me like you handled it perfectly! You were direct, yet not confrontational; you were respectful yet not "blue-nosing." You handled things just perfect!
They would be nuts if they didn't promote you! That's what I think, and I know I'm right! LOL
I hope you yourself feel good about the interview. You should ~ you really did handle things just great. So sit back and relax, and try not to obsess about it or worry. I think you should get it, but even if you don't I want you to know that you couldn't have done anything any better! If they choose someone else, it's either nepotism, or just plain politics.
God bless and keep us posted, will you? I'd really like to know what happens! Hugs, Lee