Welcome
1st you have a tortie. They have a lot of attitude most of the time.
2nd simply the fact that it is a girl will more than likely make introductions more difficult.
3rd you really need to give them more time. We are talking weeks (possibly months) not days.
4th any new addition should be able to have their own separate space when they first arrive. A room shut off from the other cat at first. The resident cat will sense its presence and help to get her used to the idea of an intruder before actually coming face to face.

If you try it again let us know as I am sure we all have some tricks to introducing a sibling.