On paranoia Take gains and losses with the same indifferent reaction. Why are you worried at all at the possible downturn of anything? Your paranoia will only serve to make a poor outcome more likely. If a book succeeds and sells hundreds of thousands of copies, you shouldn't react whatsoever. Think Bill Belichick. However, that's because it prevents you from having to react if you don't sell hundreds of thousands of copies (because you won't.) Even better, it prevents you from being a downer if success is ever taken from you through force or sheer unluckiness. If you at any point allow your desire to be strong, you lose leverage because what you desire can be taken from you. I see how that's happening, so make it stop. Immediately—otherwise, you will lose it all. That's not me telling you to be paranoid.
On history Of the greatest creators to ever live, how significant were their lives in the scheme of all history? How many of them can claim to have been different than the rest of the world? None of them, for they all suffer the same fate—death—and leave themselves to the whims of the future that will replace them, just like they did the past they were faced with. So far, this sounds gloomy, but it's all to say—if what they did was so insignificant and small compared to the rest of the world's history, what excuse do you have to not make similar things happen? Perhaps that won't be your express purpose as you do it, but history shouldn't discourage you. These figures you look up to are the same type of human you are. Dylan dealt with heartbreak. Jobs dealt with perfectionism. Chanel dealt with a lack of satisfaction from her work. What will make you any different? Either, one, nothing will make you different except for the impact you create, or two, you will find a different path to satisfaction and fulfillment that doesn't involve creation or works. There's a solution, though you'll be hesitant to accept it as so. It may even lead you to the same place as some of these great people, but the path you use to get there will create a far different legacy. It might also lead to a life of mere humility and no recognition along with it. You'll have to accept that, which I foresee you having trouble with.