dominating and stubborn behavior

Question
QUESTION: I have an 8 weeks old black labrador pup. he has pimple like eruptions near his genital which it keeps licking time and again. i hope its not a disease as it is covered with part hair.
the pup also keeps on biting its right hind leg paws time and again , when i try to look at it by feeling it , the pup makes a sound as if its in pain. i hope its not a serious problem as it looks.
thanks a lot for helping me out on this.

ANSWER: I would take the puppy to a vet.  This sounds like something that you would have to see to give an idea of what is wrong.

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QUESTION: my 12 weeks old labrador pup has a very dominating and stubborn behavior , he sometimes humps my leg and i push him away as he doesnt listen to me on this other wise i am training him and he is responding really well , he bites and barks at me whenever i try to pet him ,only time he doesn't do it is when he gets up from sleep and is still half awake half sleepy.
please help me on this

Answer
The pup is 12 weeks old.  It's not really being dominant or stubborn.  It's being a puppy.  If he humps, tell him NO and redirect his attention.

This is also a great time to start obedience class.  This will help with him listening to you and learning that you are the leader.  Barking at you and not listening is usually a sign that the dog is not picking up good "leader" vibes from you.  You can improve this by attending a class.