Stop asking yourself what if you can't do it, and instead as yourself what if you can? What if you can write a bestselling novel? What if you can accomplish your dream to be a published writer? If you're willing to work for it, you can.
I just feel like I've been waiting for the "so good" part for too long. I'm too old to still be waiting for things to be great. I made so many stupid choices when it came to careers and now I'm stuck going nowhere.