occasional aggressive 5month old male lab.
I have a 5month old lab and for what seems to be out of nowhere he will jump and bite and do this with growling sounds. He has done this mostly on walks but it has led to play time too. I tell him NO and try to get him to sit and remind him to be "nice" which is him licking instead of biting but it doesnt always work. I do feel he has a bit of a dominant side. I often feel I have to restrain him to protect myself but that can make it worse. Im scared this is aggressive behavior. What should I do?