He needs to be seen by your veterinarian and have bloodwork performed as these can be signs of parvovirus or diabetes with the vomiting and big water increase intake. I would have him seen as this is one of the first signs that you see and it is better to find out now and get him on an effect diet and treatment should this be the cause. Any sudden changes in behavior are cause to have your pet seen and since he is displaying behavioral changes as well I think the sooner you have him seen the better you are. It could be an internal parasite causing the vomiting as well but it is best to have all possibilities ruled out.
*Cheryl K* Please click the
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