It is a normal thing that you have this fear in you. The fear of failure or even the fair of success. You know you have to do certain things in your business but the fear is creeping in your mind that it's to big for you that you can't do it and you searching automatically for excuses not to do it.
If you don't go over this fear it might hold you back your whole life to reach the level you want. I set goals so big that they scare me. I fear they are too big but that's exactly the point when I grow. I know when I feel to comfortable even when I have some progress that I don't grow.
The human mind is programmed like that, we getting lazy and let things slip. That means for me that fear is not stopping me, it's more kind of a motivation to set bigger goals and to grow.
Don't let fear stop you take it as a sign because the things you fear will bring you a step closer to your goals and to success. Use it as a motivator and accelerator.