We rescued a shepherd mix from the South and have had him 3 weeks. Neutered male, 3 years old. No signs of aggression with us, but had a bad experience at Vet yesterday...had to be muzzled due to growling. He also got a little anxious during out first visit with obedience trainer. However, he’s great with other dogs, well behaved indoors, and has been gentle with our cat. I’m a nervous wreck. His aggression threw me, and now I am very unsettled around him. Worried that he is picking up on this. Any good resources out there about rescue dog adoptions, etc.?