I don't know what she is but she is just ADORABLE! as for sexing here are some pics to help
Sexing the Kitten
In kittens younger than about two weeks, it is often difficult to tell their sex. Even competent rescuers and vets can be fooled! A female kitten will have what looks like an upside-down exclamation mark, whereas a male will look more like a colon. Also, the male's urinary opening is lower than the female's and he will also have a little lump between his anus and this opening. This will later become his testicles. Another way to tell is gently squeeze the urinary opening. If the tip of the penis appears, there's your answer!
You could also post some pics of her private parts for us to try and determine. And thanks for taking her in that was very kind of you!