Thanks for asking guys. Jimmy has stopped throwing up and the hiccup like sneezy things he was doing have also stopped. I think he may have had something (like a piece of kibble) lodged in his throat or something and now it has passed? I didn't speak with the vet about it but I will when I go in next. I'm wondering if there are meds that could help break up the stone in his kidney. I don't think a diet change would work for him because he is doing so well on the Hypo Gastro food for his IBD.
Thankfully he is doing better but I will be keeping a close eye on him. He's such a special cat.