Is "amazing" your characterization of your performance at the audition? I wish people would not over-use that word, especially when they use it incorrectly.
It once took me three years. Yeah, not kidding. (And I got it)
Madame Morrible: "So you take the chicken, now it must be a white chicken. The corpse can be any color. And that is the spell for lost luggage!" - The Yellow Brick Road Not Taken
It's hard to tell. Like it's been said, it could be anywhere from a few moments, to several months (or in some cases, years).
Sometimes the casting table will say things like, "Wow, that was great," or "amazing," but sadly, that doesn't really mean much. They could be saying it just to be kind, or they really feel that way...doesn't mean you'll get the job, or a call-back. You can be great, but the wrong type for what they're casting. True, it's better than the obligatory, "Thanks for coming in," but, I wouldn't take it to the bank, if you know what I mean.
There's no rhyme or reason to any of it. I know massively talented people who don't get nearly as much work as people who are far less talented, but better looking. Just audition, have fun, do your best, and whatever happens, happens.
I have a friend who is still waiting on a call back for "Hazel Flagg." It's gotten so bad, she won't even leave the house for a minute in fear her rotary phone will ring with the news.
It depends. I mean for example, at the auditions that I've been to for shows at my college it varied. The first two shows I auditioned for there, the director had a list at the end of the audition as to who would be at the callback and I made it both times to callbacks, but never made it past it. The third show, it was a different director than the one who directed the other two shows and he called I think the day after saying that I made it to the callback and I thought that I didn't make it since they said they'd call that previous Monday, but they called Wednesday.