Change in behavior

Question
I have 22 month old male, pom-corgi mix who is displaying nervous and aggressive behavior occasionally. It has been a few weeks since it started. He is well socialized, with people and other dogs. He was neutered 6 months ago and we saw no change in behavior. We've had lots going on in our lives during the intervening months. Also, we have been undergoing remodeling for months, with strangers in and out of the house and I believe one incident of the electrician scaring him with his work-booted foot. He roughly pushed the dog out of his way at the door.  Loud noises, moved walls, things in constant flux...the dog was definitely frightened and displaced at times. He seemed nervous recently. The first aggressive behavior was a mild growling and movement (not really snapping) toward a quickly moved foot. We thought he'd get over it in a few days. Yesterday he started growling at a guest when she moved toward him as my daughter was petting him. Moments later he went to the guest, sat by her on the floor and put his head on her knee in a submissive, pet me way. Last night he reacted in a similar way with me but immediately whimpered and touched his head to my hand affectionately. He is healthy, affectionate, gets a good amount of exercise and is well behaved in the house-no destructive behaviors. He seems almost confused by his own behavior. He is a picky eater and sometimes I wonder if that affects his behavior.
Is there anything I can do before taking him to a trainer/behaviorist? I am taking him to the vet next week for a check up just in case but don't think it's that type of a problem.

Answer
I really think a trainer or behaviorist is your best bet. Plus the vet check-up. The contruction could certainly be part of the problem, but it's hard to "see" the dog over the internet. And the earlier you get good help for intervention, the less ingrained the behavior.  I would not correct him for growling, as growling is communication. If you punish the growl, he may stop doing it, but it won't change his emotions, and then you can end up with a dog who doesn't tell you he's worried until he is to the point of having to bite. Sandy Case BFA MEd CPDT www.positivelycanine.com