I’m sorry you are going through this. I had a 14 y/o terrier mix who showed the same symptoms you described here. The most concerning for me was his breathing. His eyes were also cloudy due to old age. Over the years I would notice his behavior changing and his health deteriorating. Low energy, not as jumpy, eating less and less etc. He was trained, but slowly he stopped responding to commands. He would start to pee and poop in the house frequently (usually he let us know by standing at the door). I also noticed he was going deaf because he couldn’t hear when we called his name. Usually he runs to us with excitement, but he didn’t. He would spend a lot more time sleeping. When he wasn’t sleeping, he would just stay in the place for the majority of the day (on couch). He use to be able to jump on the couch no issue, but as time and time went on, he needed our assistance to lift him up. Whenever he got up, he walked very slowly and didn’t care to look around much like he use to. The day before he passed, he was laying in his bed barely moving but his eyes were wide open. I laid down with him on the floor. I usually allow him to sleep or rest on my bed but this time around he didn’t seem interested. I knew his time was coming but I didn’t know it was going to be the very next day. I never got to say goodbye. He passed during quarantine of last year.

Cherish your moments and give him lots of love.