What sounds like a perfectly sensible question invokes other questions, like „what is a disease?“ There are, inevitably, lots of definitions, even „official ones“. Those won‘t help you.

If you were interested in the question the reason may have been that you wonder if you are going „nuts“, „crazy“, or „insane“. Most likely you are not. At least if you have a hunch as to what the reasons to your feeling „off track“ are — like a new job, boss, or project, which cause you trouble, or „feeling trapped“ for whatever reasons. (The above does not hold if you think the rest of the world, the Tibetan secret service, or Muhammed Ali have personally singled you out to deny you what you deserve. That would be different.)

There are two established schemes of mental disorders: The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), prepared by the American Psychiatric Association (APA) and now in its 4th edition, and the International Classification of Disorders (ICD-10), prepared by the World Health Organization (WHO) and now in its 10th edition. Only the ICD-10 lists burnout, but as a mere fringe category without much definition. If only for that reason, doctors will be reluctant to you use that diagnosis.

Burnout is probably a „normal“ adaptation reaction by an overstressed individual to situations he or she experiences as overtaxing. Not a disease! But causing a lot of suffering.