6 month whippet puppy- severe biting / lead biting on walks
I have a 6 month male whippet puppy called Gus and just looking for some advice.
Over the last two days, at least once a day (usually in the evening), he has an episode of about 5-7 minutes where he goes absolutely mental on the lead. He starts biting the lead, but also biting me really badly- he jumps and lunges and bites my feet, legs, stomach and today he jumped so high he has bit me really badly under the armpit to the point its bruised and bleeding. It's relentless jumping and biting to the point I've fallen into parked cars. I can't hold the lead at a distance because he jumps and bites my hand, I can't stand on the lead because he bites my feet and I can't ignore him because its constant biting. He won't follow scattered treats, or respond to any simple commands like sit or touch which normally calm him down.
I haven't identified any particular trigger (ie. not other dogs, cats, a particular place or behaviour) and if anything we will seem to be having a great walk. Today for example he did great leave it training, and loose lead walking, and then he just switched. He had also just been sleeping before we went out so I don't think he's overtired. However, this does normally happen in the evening, and when we are walking on the pavement. It doesn't really happen at the park or in the mornings.
Apart from these 5 minute episodes he doesn't show any other forms of aggression or biting throughout the day apart from occasional l normal puppy nipping when play gets too exciting. Throughout the day I try everything I can to keep a good routine- he has regular toilet breaks, some enrichment activities, short training and some gentle play sessions and he has enforced crate naps (I try to make sure he isn't awake for over 1.5 hours).
I'm getting really upset because in the moment it feels like there is nothing I can do except stand there and get bitten and I feel like its only a matter of time before he can reach my face or before I accidentally drop the lead or something (because the biting hurts so much) and then he is in danger and I am scared to walk him at the point. I'm scared he is becoming an aggressive or really reactive dog- he does stare a everyone that goes past us, so I'm wondering if he is just constantly over stimulated on walks?
If anyone has any advice that would be really appreciated, or even in identifying what the behaviour might be (ie. is he just exteremely over aroused)
Thanks!!