I am just now seeing this thread. I am not a vet but I would venture to say since Huey had such a significant UTI that was probably a good reason why he was shaking. I know I have had UTIs before and they are not fun and can be rather painful. As I'm sure you are probably aware, some Yorkies tend to shake instead of whine when they are in pain. I'm sure the infection was making him not feel so good. And maybe he had the UTI back when the first odd episode happened. Hopefully little Huey is feeling better soon and hopefully this is what his problem has been all along. Hope you get some rest today (maybe after Huey's bath).
