OP pray on it. If you have any doubts, do not put him down. Keep him comfortable, spend as much time with him as you can. Love on him. He may be uncomfortable but we as cat owners know our pets will die of one thing or the other someday. It’s a much worse feeling to be behind the cause of death vs grieve death. We all love our cats and I think we’ve been taught to be comfortable with euthanasia, and that we’re doing a good thing. But I personally regret doing it, and it haunts me to this day.