Looks like you've gotten a lot of advice already.Â
 I just saw this and I replied to a similar post on another board except it was for a Dane puppy. It seemed to fit your situation as well so I figured I'd crosspost my answer here too. Just substitue Kitana instead of Thor.Â
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My favorite dog training mantra is "Interrupt, Redirect and Praise". This works especially well with young puppies, but usually works for all dogs.
First pick what behavior you WANT him to do. Dogs have an easier time learning to do something than NOT to do something. So as an example I'll just say you want Thor to lay down instead of biting. For interrupting I say "AHT!" in a stern voice, it seems to work better than "NO" for me.
So if Thor came up to me and started nipping/biting I'd say "AHT!", tell him to "down" (or lure him if he's still in training), make him stay for 30 seconds to a minute, praise him THEN release him. (Remember to praise before releasing or he'll think he's good for getting up). If he gets up before I said so, then I'd just make him lay down again. He'll learn quickly, though it does take repetition, especially the first couple times.
Some people choose to give the dog/puppy a toy to bite on instead, which works well for other people. However, I wanted to teach them self restraint too, so that's why I did the down/sit first. I usually gave them the toy after I release them so they didn't make the connection "bite=toy".
Good luck and remember, different methods work for different dogs. Take it all in, use what works for Thor and store the rest for possible later use with other dogs.
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I think you can do it April. Kitana seems like an extremely intelligent dog who needs stimulation. I think that working in a lot of obedience work would probably help calm her down a bit as well as teaching her a "settle" command. Brain work tires them out as well as exercise and its a good idea to use them together. If people rely only on exercise, then they aren't really teaching the dog to control itself.Â
Another thing is don't underestimate her, puppies can learn "wait" and "settle" fairly easy. Expecting too little can sometimes be as bad as expecting too much. You just have to find that happy medium. Good luck with her hun!Â