Why is she ignoring me?

Whoa boy slow down! She probably did have something that came up that needed her immediate attention and by you asking her all sorts of questions about it probably sent up a red flag that you are clingy and needy which is a major turn off for most women. You need to take a few steps back and take a breath and let her breath for a moment. Starting a new relationship that will last doesn't happen over night. She is probably taking time to let things settle down for a bit. The slower you move in the beginning of a relationship the longer it will last. You don't want the newness to wear off so quickly... give her about a week, let her call you or text you. The ball is in her court now. You don't want to chase her off by being overbearing.