#phobia

Kopophobia - Intense and irrational fear of physical or mental fatigue. From the Greek word kopos (fatigue), people with this phobia (fear) go to great lengths to avoid feeling tired, often out of a traumatic past experience with fatigue.

Smile Big Smile (static.klipy.com)

I went to the Dentist today, had 3 fillings and as I have a real dental phobia I am feeling good that I conquered that (for today at least)