Your subjective, specific belief about your ability to meet the demands of a particular situation is called

It is called "self-efficacy".

Albert Bandura has characterized self-efficacy as one's faith in one's capacity to prevail in particular circumstances or achieve an assignment. One's feeling of self-efficacy can assume a noteworthy part in the way one achieves objectives, assignments, and difficulties. Expectations of self-efficacy decide if an individual will have the capacity to display adapting conduct and to what extent exertion will be supported despite challenges.