When planning for a competition or an event that will test performance it is helpful to differentiate between real and perceived limits.
Real limits are those things that are either physically impossible at this time, are physically impossible permanently, are currently lacking in skill development, or are emotionally beyond reach. There is something calming about recognizing these limits.
Perceived limits are the angst-ridden limits. These are things that feel impossible but are possible. These are skills that have been developed but are unused. These are emotions with unpleasant yet inaccurate correlations.
Instead of burning energy on inner-conflict, make a list of real vs perceived limits.
Choose 1-2 alternate plans of action to "answer" attacks on real limits.
Choose 1-2 perceived limits to address per event or per season. Practice the experience of breaking through the perceived limit.
Then go compete in the event.