Dog keeps biting my hand then turns into a human

So I had a dream that I was living in a new house with my girlfriend who I live with right now we have been together for a year and a half . I had a Doberman with the chain collar in my front yard I went to confront the dog to see if it had tags and it kept biting my hand and latched onto it at one point . I told my girlfriend to go grab my gun and for some reason she didn't . So I walked to my truck with the dog attached to my hand . Grabbed my gun and when I looked back it was still a dog. Then all of a sudden when I turned back around to load the gun it became a human with a bald head and tattoos on his neck . And without thought shot him in the head. He stayed alive then he said something and pulled out a gun . Then my dream ended . Is there a meaning behind this ? I would never shoot a person without reason . And by reason I mean if they were endangering my family . But why did he turn into a human ?