Never,ever physical punnishment. NO NO NO NO NO! You could very well make things worse.
I found with my boy when he was a nippy puppy sound diversion worked really well. (I ruind a pot in the process though

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When we first brought him home he loved terrorising my cats and my daughter, jumping on them and nipping at them, i knew we had to put a stop to it and fast because I knew he was soon to end up being a very big dog and if we let it go on somone would have got hurt.
A puppies attention span is very low, and when he started his terrorising he noticed nothing else going on around him. So I would go up behind him with a big pot and a stick, right behind his head I would bang the two together, and at the same time say Kato, Leave it! This diverted his attention to me very quickly, I would put him in the sit position and then reward. We continued this process over and over until he learned that a child running around was not his ticket for jumping and nipping, but a time that sitting and watching was the most rewarding thing for him to do.
Now...........daughter can run around the back yard with no worries about a now very big dog jumping around her and nipping, and the cats, well one of the cats (but thats a whole other story) can wander around the house without a dog chasing them.
The key to all of this was to get dogs attention on me not the other destraction, and then teach him by showing him and rewarding him what I expected him to do.
What I am trying to say, is taht you will get good results by rather physical punnishment for the bad, but correction and reward for the good, and in doing this you are not going to teach your dog to fear you, but respect you and your decision.
You have to remember that your puppy nipping you and the other dogs is just what puppies do, it is up to you now to re direct this behaviour and energy into something good.