Realised my pup is turning 14 years old and having a panic attack

What the title says.Basically it just struck me that time is flying by. I feel like I haven't caught up with all the things I want to do with him, haven't spent enough time with him. I feel I must make the most of this time. I'm just sitting on the floor and I can't stop crying. He's saved my life a thousand times over and I don't know if I've been able to give a fraction of it back.