It's a real experience, but not a diagnosis. A 2020 review brought together 62 studies with 14,161 participants. Reported rates ranged from 9% to 82%, depending largely on which questionnaire was used and where its cut-off was set. Rates were particularly high in studies of ethnic minority groups, and the feeling turned up across ages, from teenagers to late-career professionals. In studies of employees it was linked to lower job performance, lower job satisfaction and burnout. The authors note that it isn't a recognized psychiatric disorder, and that, at the time of the review, no published study had tested a treatment for it (Bravata et al., 2020).
The limits matter too. The studies were largely one-off surveys, half of them with students, so they can't say what causes the feeling or what ends it. For you, that means there's no test to pass and no label to earn. The useful question is narrower: what does the evidence about your work say? If the doubt is spilling into your sleep, your eating or getting yourself to work, start with the care routes below.
