He is home now and on lots of meds and a special kidney diet.
He has picked up no end, and his breath no longer smells.
I go back to the vet tomorrow but have just noticed a large lump (almost egg sized) on hte back of his neck. it is soft and doesnt worry him if i press it.

im hoping it is maybe a reaction to an antibiotic injection as it is in the right place at the scruff of the neck.