Chinchilla emergency

Unfortunately this is my first post. The past 3 days my chinchilla has not been eating or drinking so I took him to the vet yesterday. we found out he was constipated and had a fever of 103 he injected him with some fluids and sent us home with a laxative and a prescription for apples lettuce and carrots. The vet said to try and feed him this stuff in the morning I've been trying to hand feed him but he still won't eat or drink an he keeps stumbling all over, thrashing, an shaking almost like a seizure. The vets office is closed for the weekend and I don't know what to do I have work soon and I'm scared to leave him alone