Doctor got out of bed in a bad mood (6)
I believe the answer is:
morose
'in a bad mood' is the definition.
(morose means sad or in a bad mood)
'doctor got out of bed' is the wordplay.
'doctor' becomes 'mo' (medical officer).
'got out of bed' becomes 'rose' (rise can mean to get out of bed).
'mo'+'rose'='MOROSE'
(Other definitions for morose that I've seen before include "Sullen, crabby" , "blue" , "Down in the dumps" , "Sullen and ill-tempered" , "Sullen or glum." .)