*(I write this in response to some dojo'ers that had mentioned to me that they sometimes can't shake doubt. My answer has always been that doubt is 'the lightest form of fear' so don't attempt to shake it, understand it and it vanishes.) 'from the book, 'Standup Comedy with a side of Chili'.
~Doubting yourself is simply being human. It's just a dream of sorts. Understand that and you won't ever allow it to grow into fear that will make you submit to inaction.