This is all normal When he has something he shouldn't (paper, plastic, etc.) remove it and give him a proper chew toy in its place. He is biting because you are taking something away from him and he is left with nothing. As for biting your hands and growling, this too is playing. If the dog does this it is more than likely because he wants to play and feel lonely. I suggest getting a toy he loves and tossing it for him.I think He is getting aggressive , Some times he just jumps on the sofa and starts biting my hands and growls and barks if I resist , sometimes after I remove something in his mouth eg paper he starts biting ..