Different kinds of "confidence" both of which can occur. What you describe is a more manic "the world is centered on me" kind of egotistical confidence. The o

Different kinds of "confidence" both of which can occur. What you describe is a more manic "the world is centered on me" kind of egotistical confidence. The one the OP describes is more of a "I survived everest so I can surmount this challenge" kind of confidence. I'd argue the latter is more common in healthy use. The former arises from abuse. Either abuse of frequency, or not really taking care of yourself properly before/after a trip (like pulling an all-nighter or similar silliness). It sounds like your coworker was taking it with some regularity, potentially to perpetuate that sorta manic state.