I was looking at my LinkedIn profile (which I don't think anyone actually uses) because they want to link to us from work (which I'm not comfortable with, and seems to put your people on the market, but whatever), and it occurs to me that I have an awful lot of experience.
I saw somewhere recently that it takes about ten years of doing something to be truly good at it, whether it's making music, working on cars or programming. Naturally that's a big point for me because I've been doing this programming thing for about ten years. I still feel that I have a great deal to learn, which is what turns me on about it.
All that said, if I look at my resume, I realize just how diverse and rich my experience is. It serves me every day at my current job. It serves others when I give them advice.
With my tendency lately to constantly question myself and my ability, I need to fall back on this. There's a pretty good story to tell, and a great deal from me to draw on regardless of what I do. Being down on myself is a mistake.