How horrible! I'm so sorry he is so sick. I would also get him x-rays immediately to check for a blockage. I don't usually say anything because most feel greenies are fine, and most of the time they seem to be, but if he DID gulp any larger pieces it could have caused a blockage or partial blockage and it could indeed be causing his problems. Of course I hope he just gets better, how horribly sad since he just came to join your family, he seems like such a sweetie. I know how you feel with regards to a new dog having so many health issues, I almost lost Ginger the first month I had her too and had 800 in vet bills within the first two weeks to try to save her, and another 400 the next month in vet bills. I will pray you have the same outcome we did and he turns out to be okay. Prayers for you all!