This is because overthinking as a trait is very good at tricking us into feeling worse about a situation than we should. Our lives are not how they were thousands of years ago where fears were while very real, and much more well-defined than "I'm stressed over exams" back then our concerns dealt more with finding food, avoiding the warring tribe next to us, or getting the hell out of dodge, when we find ourselves face to face with a lion that thinks we may make a good snack.
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