There are all sorts of possibilities as to why he missed your appointment. It is possible as someone suggested that the emergency had already ended when you saw him shopping. You will never know until you talk about it.

I know I would have a hard ti me bringing it up too. My nature would be to just let it ride but that would not really be the best. You can do it gently and give him a way to save face rather than grinding his face in the dirt with confrontation.

Unless you are totally willing to put it out of your mind forever, which would seem unlikely for most people, talking about it would be far more productive and give you the resolution you need