Mark Twain is rumored to have said something along the lines of "Eat your frog" (it may be apocryphal, but whatever: http://quoteinvestigator.com/2013/04/03/eat-frog/). The point is that you should get up in the morning and make a point of doing the worst, most boring, most disgusting task you can think of. And don't think too hard, just get it done. You can decide whether to improve on it later. Then, the rest of the day, you'll be freed of all the worry, wallowing and indecisiveness.

The other thing is that if they value you, it's probably for a reason. You're fulfilling their expectations and providing them with value. Take the compliment and go with it! http://en.wikipedia.org/wiki/Impostor_syndrome