Without knowing the extent of the injury all I can advise is to try to keep her quiet and calm and monitor for any trouble breathing or discomfort. Signs of breathing difficultly, trouble walking, dissension of the abdomen, bleeding, changes in attitude that include panting, inability to get comfortable, or any sign of distress warrant an immediate trip to the closest emergency clinic. Please see the vet tomorrow and I expect they will do a thorough exam and provide pain medication (please don’t use an over the counter without the vets ok), and antibiotics.
Well, it may or may not be bad; depending on how strong his system is. Butter is not toxic but it is, clearly, very high in fat. So the biggest danger from consumption of so much of it would be pancreatitis. I imagine some dogs might eat all that and just get a mild stomach upset. Others might get in a lot of trouble. Pancreatitis is painful and can be dangerous. If he’s still vomiting and/or looking ill, do see a vet asap.