If you are paralyzed by fear you should considering assessing and quantifying the risks.
1. Identify the risk. Describe it in detail and document specifics.
2. Ask yourself: "So what?" You've identified a risk, but assess the implications of the risk. For example, if your business doesn't bring in enough income you won't be able to pay your rent.
3. Consider ways mitigate the risk. If your business isn't covering your rent, how long are you willing to wait? If it's 6 months, then you'll need 6 months of rent saved before launching your business.
4. Implement the "control" and stay on your plan.
5. Evaluate your plan, and make changes as necessary. If you reach the end of your sixth month and your business is still not generating sufficient revenue to cover your costs and pay your rent, then it might be time to begin the process again.
Some risks will threaten your business, and others will threaten your confidence and ego. Both types can and should be considered and mitigated. By doing so you can face your fears and take positive steps to move forward with your dreams.