Pregnant rabbit?

I just got a rabbit from the spca, she has stated to build a nest with bits of her fur and hay, is she pregnant?
Also she is aggresive, I did my research and have provided her with everything, but after having her for a couple days now, she started to growl and tried to bite me a couple times when I tried to pick her up to go back to her hutch from being out doors all day.
She won't leave her hutch on her own either, and I would like to get her out of there for exercise and to clean the area.
help please.

She sounds ready to deliver, rabbits usually build their nest a day or so before birthing, dont disturb her for the next couple of days and definately dont touch her nest, if indeed she is preggers, in 3 or so weeks you'll see little bunnies coming out of it.
Most important thing now is keep her free from drafts and let her do her thing.