Was about to get worried (9)
I believe the answer is:
concerned
'worried' is the definition.
('concern' can be a synonym of 'worry')
'was about' is the wordplay.
I cannot really see how this works, but
'about' could be 'on' (as in a book 'on' a certain topic) and 'on' is present in the answer.
This may be the basis of the clue (or it may be nonsense).
'to get' is the link.
Can you help me to learn more?
(Other definitions for concerned that I've seen before include "Worried, anxious" , "Feeling or showing worry or solicitude" , "Involved - worried" , "anxiety" .)