Where nurse may be heading is unfortunate (8)
I believe the answer is:
untoward
'is unfortunate' is the definition.
(thesaurus)
I can't explain the rest of the clue.
Can you help me to learn more?
(Other definitions for untoward that I've seen before include "Adverse - inconvenient" , "Unexpected, inappropriate" , "Improper" , "Unlucky" , "Adverse - out of the ordinary" .)