Yep - I have a teenage son - introverted, very bright (dark hair, too many cowlicks) - who is completely inarticulate about his feelings. I don't pry - I know from growing up with a brother that prying is totally counterproductive - but sometimes he voluntarily talks to me and I actually think he doesn't know half the time what he is feeling, even when it is really strong!

I don't understand how he can just not look at the seething feelings roiling about under his skin even as he is feeling them. His younger siblings are far more self-aware. Personally I'm of the 'analyse it six ways from Sunday' style of emotion management! :)