The behaviors your dog is exhibiting are more accurately called resource guarding and/or possession aggression.
Given the disparity of the size differences in your dogs, you need to make sure that anything of value to your Labradoole is kept put away. You also need to get a trainer in ASAP for an in-person look at the situation. Your vet should be able to recommend someone. It's possible your vet will recommend a veterinary behaviorist, which would be even better. That's a licensed veterinarian who specializes in behavior issues. As I'm sure you realize, your Labradoodle could easily kill your Pap. Easily.
Your Labradoodle is also in the period known as canine adolescence. It's the period of time when a maturing dog, like a human teenager, gets moody and wants to push boundaries. You need to get a plan and develop some structure, just like a human parent would during this time.