I lost my kitty a few months ago to kidney failure. I didnt know how bad he was until the last few days....he was fine and then all of sudden he wasnt. I decided to have him put to sleep as the costs were gettin so insane and he was getting sicker. Its hard to watch your cat sick and not be able to afford all the stuff you want to take care of him. So, I know how you feel. It stinks!!! Not peeing IS pretty serious, is he an outdoor cat that he could have been hit be something that is effecting him like this? Some of these things (even if the vet finds out what it is) are REAL expensive, so dont feel bad just keep him comfortable and hang out with him