Ever feel like an impostor? That all of your achievements were just luck, and any moment people will find out that you're not as smart as they think you are? Dr. Valerie Young calls it The Impostor Syndrome.
She hits on an important point. Behind the fear of being found out (and all fear) is a limited and limiting belief that hijacks your self-confidence.
As adults, we have pretty good holds on our fear. I imagine mine are hiding in deep, dark places in the recesses of my mind. Yes, they exist. No, I don't want to think about them.
Thing is, when they are holed-up somewhere they have a lot more power over us than we realize. They turn into the thing-which-cannot-be-named, a creature so grotesque and frightening that it's best to do anything you can not to let it see the light of day. Hence, not trying something new or celebrating your latest achievement as your own doing.
It's like a battle of wills between us and our fear. Considering they were created by us in the first place, it shouldn't even be a contest. We should be winning.
There are a couple options when a demon/gremlin/fear rears its head, and one of them is to shine a light on it. That means going into that scary place where you have tucked it away and seeing it for what it really is, part of you and trying desperately to tell you something.
Once you hear what it has to say, it loses its bravado.