Most Helpful Guy
Just because he tells you about it doesn't have to mean that he wants to talk about it. It can also be because he wants you to understand if he behaves a little odd.
Many guys don't want to talk about things. Because just talking usually don't solve the problem and most guys only ask for advice or ask for help if it can help them solve the issue. They usually don't talk just for the sake of talking about it like many women can do.
What he probably is trying to communicate to you is that he is not feeling to good and he needs some space. That is why he goes quiet when you keep asking him to talk about it.