It really sounds like Major is getting bored. His mind NEEDS to be stimulated. He needs to constantly be steered in the direction of good behaviours, and tired out so that when you leave him to himself, he goes to sleep instead of acting on bad behaviours.

Puppies don't learn to be well behaved all by themselves. It takes tons of time and lots of energy and ATTENTION!!! I cannot stress this enough.

How long did you walk him today? How many times did you throw the ball so that he could run and chase it? The only well behaved puppy is a tired puppy.

If you take him out for 15 minutes, and he is still bored, take him for a 30 minute walk. When you play fetch with him for 30 minutes, and he is still acting bored, play with him for an hour.

Exercise, exercise, exercise!!!!!!!