Talk to the vet... they wanted to do X-ray, blood work, and sedate him enough to look in his mouth (check teeth). I told them that's a lot of stress on a chinchilla and would prefer they choose ONE of these procedures (whichever seems the most beneficial based on his symptoms). They haven't gotten back to me yet, but they did give me some
Oxbow Critical Care to force feed him. Poor little guy, he was mad at first, then before I knew it he was leaning toward the syringe...going for it...wanting more!
...which makes me think it's a tooth issue. He has been eating, just not much. (and he drinks water fine!) Maybe hard food is hurting him to eat, so he was all into this mush! But would teeth issues cause a runny nose? It's so weird. One doc thought he might have pneumonia, but I told her they listened to his chest on March 5th (last time we were at the vet) and said he sounded all clear.
Guess we'll see....in the meantime I'm feeding my lil guy through a syringe and he's cool with it.