First, welcome to YorkieTalk.
Has she eaten yet today?
Have you tried forcing it?
Are her gums pink?
Since Minnie is so young and this is very unusal for her and it has been more than 24 hours, she probably needs to see a vet.
Since she didn't yesterday, no pooping wouldn't be a huge concern quite yet but she should be interested in food by now. Have you tried canned?