I have a 4 month old golden retriever puppy, in the last month or so he’s recently started to become very aggressive. If you try to pick him up he will snap at you and bark same as if you tell him to stop doing something. At all hours of the night 3/4am he will wake up too to out to the garden and will not come back in if you try to bring him in or go towards him he will get very aggressive. He also constantly bites on his feet and thighs like mad. We are aware he’s having anal gland problems recently but the aggression is not from this as it started way before. If anyone has any idea what might be wrong it’d be a great help thanks.