Both restlessness and shaking are symptoms of many conditions. Shaking and restlessness in dogs are usually due to pain and discomfort. Pain can occur due to traumatic injury, inflammation of the tissues, and some diseases. Bloating in dogs also causes restlessness. Treatment depends upon underlying cause. So, take your dog to vet who will go for complete examination, blood tests, urine test, abdominal X-rays and ultrasound for proper diagnosis and treatment.
Shaking, shivering and restless in dogs is usually associated with Pain which can be due to muscular and skeletal problems, disc injury, traumatic injury, damage and inflammation of the tissues, exposure to heat and cold, and some diseases. Fleas and skin parasites can also cause shaking or shivering in dogs.
Another possibility of shaking and restlessness is nervousness. If your dog is nervous then also he/she can be lethargic, shaking and angry. So, it will be better to take your dog to vet and discuss these problems for exact diagnosis and most accurate advice.
Restlessness is many a times due to some underlying fever or tick infection too. Like mentioned above, get your dog to the vet and ask him for the tests needed to rule out any tick or other infection. Other causes of restlessness could be indigestion...if he spits out some yellowish sputum or is trying to push out something from his stomach while lying down, you might want to ask your vet for an antacid such as ranitidine shot or digene.
