When a dog has a fever, its body temperature will rise, and it will become unwilling to move and feel depressed. You should give your dog some antipyretic medicine and let it rest well.
If the appetite decreases, try to feed the dog some high-calorie and easily digestible canned food to maintain its strength; Its nose will also be dry and hot, it will have shortness of breath, and its belly will be red. If the symptoms are serious, it needs to be sent to the hospital for treatment in time.