Well, dogs cannot tell time like we can. When we are gone and they are left alone, they can stress and three hours can seem much longer to them than we realize. After all your dog is still a puppy, much like a child and it takes them time to truely learn to relax and know you will be returning. Your supposed to be the alpha entity to the dog and they truely don't like to be left alone, it takes time for them to truely get used to being alone. It would be interesting if you knew how long the puppy did wait before pulling the blanket across the floor and peeing on it.

I know that my dogs can sense my husband is coming home a while before he comes home, they do sturr and sit by the door excited long before I hear him pull up the driveway. And this one is hard, my husband goes to a meeting every Monday night and usually he works nights and doesn't come home til later except for this one night.
My dogs seem to know the difference between this night and the others and that my husband comes home much earlier. I honestly don't know how they know.

Open Eyes