Tired, due to being drilled? (5)
I believe the answer is:
bored
This clue is a double definition.
'tired' is the first definition.
('bore' can be a synonym of 'tire')
'being drilled?' is the second definition.
(I've seen this before)
'due to' acts as a link.
(Other definitions for bored that I've seen before include "World-weary" , "Fed up, afflicted with ennui" , "Wearied by tedium" , "Pierced" , "Robed (anag.)" .)