If she senses you are afraid of her then she will try to be the Alpha over you. You need to let her know that that is unacceptable behavior. I do the ouch thing if she is nipping in play. I will actually put the dog in a time out if it is done in a manner that is not nipping in play (which I think you described).

Take the dog and leash her to a door knob or somewhere where you can tie her up. Not the crate since you are crate training. When she settles down then you can go back to her. I would also really start to hand feed and do basic commands before she gets anything. Even her tennis balls and toys! You can even get her to sit before she goes out for a walk. NOTHING in this pups life should be free! She needs to learn that YOU control the situations!

At this age the worse thing you can do is to let her sense you are afraid. Get her into a puppy kindergarten class immediately. The instructors of most classes are very knowledgeable and may be able to offer additional advice. Make sure it is a positive based class and not one that uses pops and chokes. Pops and chokes on a dog who shows aggressive tendencies can back fire on you especially if they are not done correctly.