My Boston shivers when he wants food ... Or if he gets excited. They love to cover up also because they tend to get cold faster then other dogs. The shaking is normal for them I think.
Boston Terriers have a lower body temp than other dogs, which is why bostons love to be under the covers. Either the dog is cold and trying to raise its body temp. Or they have done something wrong and they know it. My Boston shakes when he has used the bathroom on the floor and he knows I will be upset with him. He tells on himself every time.
Boston Terriers do get hold quickly. They loved to be covered and always snuggle with you to keep warm. My Boston will also shiver if he is in trouble and he knows it or if I am leaving he sits on the stairs and shakes.
Lots of different terriers shake , it's just a normal thing for terriers.