HELP! Totally new personality after 2nd heat.
My GSD, Isa, is a 15 month old female. She has always been a submissive dog (the one when other dogs rush her, she would "go to ground" and cower). She has always backed off when the two other dogs in our family (elderly beagle and elderly pit/lab mix) gave warning growls or nips.
Suddenly, starting partway through her 2nd heat, she occasionally turns on the beagle and just this week with my daughter's female dog who was home visiting (these dogs have been together frequently since Isa was 8 weeks). Generally it has happened when the other dog plays too rough or when the beagle growls that she has had enough of Isa's face licking. It's very scary. I can barley get them separated. I'm just shocked. Isa has always been such a loving, sweet dog who never growled or showed any aggressive tendencies at all. Her biggest problem has been barking at strange dogs, but once she "met" them she was always friendly and eager to play.
Isa has been well socialized. She has been in classes since her last set of puppy shots (14 weeks?). She always travels with me, goes to restaurants, stores, the bank, etc. She plays at a neighbor's house several times a week with his dogs (all male). She doesn't react to motorcycles, wheelchairs, skateboards, garbage trucks, balloons or people of all ages and sizes. I'm very concerned.
I have called a private trainer we have worked with some (he helped me train her to invisible fence and worked with her on barking at other dogs) who is coming to the house in 2 days to see what he can do/see here.
The only reason she has not been spayed is that she was diagnosed with IBD and had such a weight loss, vets did not want to do surgery until she was stabilized. She has gained back most of her weight and is scheduled for spaying in December (vet school advocates waiting 60 days after a heat cycle).
Any thoughts, suggestions? I hope someone can make me feel more optimistic about this. Right now I feel like an alien has invaded my dog!