Please can someone help! I have a 3 year old male labrador. He is overweight and was told his mother was over bred. We’ve had him since a puppy. This year he has collapsed 3 times. He will put out his front legs and start yelping and crying as if he’s in pain. He can become aggressive if touched he does not bite and never has done. He will show his teeth. Why is he doing this??!! Please help it’s heartbreaking!