If you ask a person what he feels, the answer will be happiness, irritation, joy or other emotions.
In the case of a dog, everything is much simpler. They express emotions through facial expressions and postures. Looking at the dog’s face and how it sits or stands, you can understand how it feels.
If the dog has relaxed muzzle muscles, eyes are rounded, the mouth smiles, then the dog doing well. If at the same time it wags tail and looks at you, then your dog extremely happy to see you and ready to communicate and play.
And if the dog is uptight and looking at something on the side, then most likely there is something bothering it. Subsequently, this can become aggression or fear. If something scares the dog, then it raises its tail and goes back. If something pushing it into a corner, then it will show aggression. The state of aggression is manifested in the fact that the pet raises its tail, stands on its front paws and lifts the back of the body.
Watching your dog and paying attention to the signals that it gives you can help to understand what it feels now.
The important thing is that the owner must determine the signals of stress. In moments when the dog shows that it is feeling bad, uncomfortable and that he is not ready to play and train now, you need to see this and act following this state.
For example, if a person feels discomfort, then it will be difficult for him to concentrate on solving a problem. That is why for the doing commands and playing with the dog you need to be able to see his condition and in case of stress - provide comfortable and calm circumstances.