I have a 14 week old yellow lab i am trying to train. The problem i am having is while trying to work with him all he wants to do is run off and not listen i tried fetching with a leash and he sometimes will pick up the bumby and sometimes if he does pick it up he tries to run off with it. He doesnt listen at all i have another adult lab in the same area as where i work him and all he wants to do is play.Is this normal for a puppy to act like this and at what age should i start to see him be more interested in learning than playing.