Worried having to work longer hours? (8)
I believe the answer is:
restless
'worried' is the definition.
I don't understand how the remainder of the clue works.
(Other definitions for restless that I've seen before include "Worried and uneasy" , "Unable to keep still" , "Fidgety - unable to sleep" , "Not relaxed, unsettled" , "Fidgety, uneasy" .)