Anyone who sees me in action taking pictures at an event or interviewing people would probably tell you there's no way I'm a shy person. I can be as charming or even gregarious as I need to be.
However, without a camera or a reason to be there and talk to people, I am as reluctant as a wallflower. Except, of course, when overwhelmed by curiosity, which seems to be a genetic thing with me. Even as a kid I would interview people -- without realizing that was what I was doing.
While journalism is no antidote to shyness, and the crippling variety (of shyness, not journalism) requires more than a pen and paper in hand to cure, I wouldn't recommend ruling out journalism just because you're shy.
If you're functionally brave -- okay when you have a task to do -- there's no reason to let self-consciousness keep you from becoming a writer. As long, of course, as you have your other talent ducks in a row -- curiosity, expression, the capacity for accuracy, and the other things needed to be proficient.
The other thing is, if you're uncomfortable asking difficult questions, you can always do the kind of writing that doesn't demand them. There are plenty of opportunities out there for stories that don't involve digging for dirt, looking under rugs or any other of those "unpleasant" and investigative metaphors.
While some of us are news buzzards, able to sniff or spot a story from a distance, others are simply builders. Like robins or songbirds, basically there to do uplifting things like sing songs and build nests. There's feature writing for newspapers and profile writing for trade publications, for example. Takes all kinds.
Here's a link to an interesting blog by Cary Tennis of Salon about someone who's grappling with shyness in journalism.