Another thing that struck me...I mean, don't get me wrong...I learn about dogs through reading a lot...so I don't even nearly know as much as the other people here...so maybe my thought is wrong or simply doesn't really matter
But you said your tutor was over and your dog was all over you and the tutor...can't you crate her..maybe still in the same room? If your puppy knows that he/she can do whatever pleases her/him (sorry I forgot), it may be harder to get rid of that biting and training her.
My puppy was a biter, too...but I did the same thing Pixie suggested, leave the dog alone and ignore her for a while. Then return and play...if it happens again, leave again.
But you said your tutor was over and your dog was all over you and the tutor...can't you crate her..maybe still in the same room? If your puppy knows that he/she can do whatever pleases her/him (sorry I forgot), it may be harder to get rid of that biting and training her.
My puppy was a biter, too...but I did the same thing Pixie suggested, leave the dog alone and ignore her for a while. Then return and play...if it happens again, leave again.