Watch a roomful of preschool children. They are enjoying life because they are focused on the moment and are not thinking about it. They are immersed and absorbed in living. Analysis creates paralysis. Stop thinking about it, take that step, and just do it.
Thoughts grow with attention.
If you focus on negative thoughts, they will grow and grow and become larger. Even if you understand and know why you have a problem, this will not help you in solving it. Going over and over the reasons for your problem is like pouring salt in an open wound. The only factor making you unhappy is your own thoughts. Relax, release them, let them go.