Dogs shiver as a way to generate body heat when they're feeling cold. If you notice your dog trembling or shivering during the night, it could be a sign that they need additional warmth. Dogs instinctively seek out warm spots when they're feeling cold. If your dog is constantly trying to find a warmer area or snuggling up against objects or people, it could be a sign that they're feeling chilly. Dogs often curl up into a tight ball when they're feeling cold. This helps to conserve body heat and keep themselves warm. If your dog is sleeping in a more tightly curled position than usual, it could indicate they're trying to stay warm. Check your dog's ears and nose. If they feel cold to the touch, it suggests that their body temperature may be dropping. When dogs are cold, they may become less active and more lethargic. If your dog seems unusually sluggish or less interested in activities, it could be a result of feeling cold and trying to conserve energy. Some dogs may display behavioral changes when they're feeling cold. They may become more restless, whine, or seek attention to communicate their discomfort.