Why would he

care at all?

Anger

Anger is something eveyone encounters aat some time in their lives. It is a learning thing, and to not express it is to doubt yourself. Though I have gotten angry in the past, I have almost always been able to express my feelings and try to fix the problem. To live with anger, without expressing or realizing it, is, in short, death. It ruins the lives of those around you, and even if you would normally have enjoyed this moment, you are so stuck on whatever is making you angry that you might not even notice the happiness you could be having. Anger is NOT BAD if dealt with properly. Now, if you hold it in, re-live it over and over, and don't discuss it with the source, or who you may think the source is, chances are it will get worse. It will mess up everything and more. Which is why you need to get over your fear of expression. Just DO IT. In a nice way (or not. depends on who and why) talk to the person. Deal with it.
And you may even realise why you really are angry has nothing to do with what you were telling yourself.