"How you feel is a lie" is the motto for RPE 11. An encouragement to not allow any outside stimulus effect your physical goals. Positive or negative feelings aside, all that matters is your ability to execute your lifts to the best of your physical and mental ability.
We all have feelings of doubt, "I am not strong enough" or "I am not ready to take on this challenge." We also have feelings of overconfidence. The mindset we encourage is a dedication to perform to the best of your current ability, every time you train or compete.
How you feel does not dictate success, your work ethic