It might be she just isn't used to a leash yet. Hopefully once she gets used to the leash she won't bite it. As for the pulling, we are struggling with that too. What we have done is when they pull, you stop and go the opposite direction. With Tucker, it took a long time, but he is a good walker now. There are various collars that can help too. We have used a choke chain, but I wouldn't recomend using it unless you have been trained how to use it properly. I have good and bad about Gentle Leaders or Halti's. They help keep them from pulling, but it is real hard on their snouts and it doesn't really train them not to pull when you aren't using it. The best bet is to find a good trainer and work with them. When you do work with a trainer, it is also important to practice daily.
Good Luck.