It is normal for a dog to arch its body in two months. It is an imitation behavior of the dog and is not in heat. This happens to both male and female dogs when they are young. If a dog behaves like this, it is best to stop it in time, especially for male dogs, to prevent the dog from developing a habit and causing the behavior to become more serious. You can play with the dog or give the dog other toys to distract the dog.