The best way to overcome your fear of creativity, brainstorming, intelligent risk taking or navigating a tricky situation might be to sprint.
When we sprint, all the internal dialogue falls away and we just go as fast as we possibly can. When you're sprinting you don't feel that sore knee and you don't worry that the ground isn't perfectly level. You just run.
You can't sprint forever. That's what makes it sprinting. The brevity of the event is a key part of why it works.
"Quick, you have thirty minutes to come up with ten business ideas."
"Hurry, we need to write a new script for our commercial... we have fifteen minutes."
My first huge project was launching a major brand of science-fiction computer adventure games (Ray Bradbury, Michael Crichton, etc.). I stopped going to business school classes in order to do the launch.
One day, right after a red eye flight, the president of the company told me that the company had canceled the project. They didn't have enough resources to launch all the products we had, our progress was too slow and the packaging wasn't ready yet.
I went to my office spent the next 20 hours rewriting every word of text, redesigning every package, rebuilding every schedule and inventing a new promotional strategy. It was probably 6 weeks of work for a motivated committee, and I did it in one swoop. Like lifting a car off an infant, it was impossible, and I have no recollection at all of the project now.
The board reconsidered and the project was back on again. I didn't get scared until after the sprint. You can't sprint every day but it's probably a good idea to sprint regularly.