You searched for: “imponereophobia
imponereophobia (s) (noun) (no plural)
A distress at being found out that one is an imposter: In the story Susan was reading, the main character turned out to be a sham who gave pretences at being what he wasn't, and suddenly, when he was discovered as a deceiver, he had a case of imponereophobia, with the typical symptoms of a fast heart beat, sweating, and a panic attack.