Cotard's Syndrome

The Cotard delusion or Cotard's syndrome, also known as nihilistic or negation delusion, is a rare neuropsychiatric disorder in which a person holds a delusional belief that he or she is dead, does not exist, is putrefying or has lost his/her blood or internal organs. Rarely, it can include delusions of immortality...

...it's just one of those days...