I'm having two major problems with my corgi right now.
1. Chewing. Oh, God the chewing... It's getting out of control.
2. Interacting with other dogs.
Roxy is almost a year old now (1 year old on 8/10) and for the most part, we never had these problems until recently (the past month).
As far as the chewing, it just seems like she destroys everything she finds. If it's in corgi-reach, it's hers as far as she's concerned. She really seems to like pulling books off shelves and eating them. We try to keep things off the floors, but no one is perfect. Sometimes she even goes out of her way to pull things down. She hasn't gone for furniture very much, fortunately.
She has plenty of toys (10). I picked them based on the textures and colors she likes best. She seems to love red and orange and dislikes cool colors like blue or purple. There's also a couple of intellectually stimulating toys in there to keep her curious and challenged. I alternate her toys and their location in the house three times a week to keep her interested. Despite all this effort, she still seems to largely prefer chewing things that are not her toys.
I don't really "punish" her for chewing things because I've learned that it doesn't work. It only seems to make her fearful. If I catch her in the act, I will say "No chew!" in a louder than speaking volume, with deeper pitch and make sure that she associates it with what she has just destroyed. I will do the same thing if I don't catch her in the act, but less firm, since dogs don't understand too well what they're being yelled at for unless they're caught doing it and corrected immediately.
As inconvenient as this may be, it doesn't worry me as much as how she's been acting around other dogs lately. When she was a younger puppy, she loved interacting with other dogs. We took her to puppy class at 3 about 4 months of age and had no issues with any of the other dogs in the class. I even took her to dog parks starting at 8 months and she loved it.
Unfortunately, she's been acting oddly around other dogs lately. I noticed it two weeks ago when I took her to the dog park. She was shying away from dogs and growling if they wanted to come close enough to play. This is a complete 180 from her old personality. When I walk her, I notice that she's very eager to meet other dogs, but once she does and they try to play, she gets aggressive.
What's going on here? I recently saw our old trainer at Pet Smart (where she attended puppy training) and she said that between 10 to 12 months dogs go through something like a teenage phase where they test boundaries. Likewise, the breed book says that dogs go through a "fear phase" at this time.
So, should I expect this to pass? What signs should I be looking for? Any suggestions on what I should do to help her (with either issue)