Discomfort in AA? Smile falsely (7)
I believe the answer is:
malaise
'discomfort' is the definition.
(malaise is a kind of discomfort)
'aa? smile falsely' is the wordplay.
'falsely' is an anagram indicator.
'aa'+'smile'='aasmile'
'aasmile' is an anagram of 'MALAISE'.
'in' acts as a link.
(Other definitions for malaise that I've seen before include "flu perhaps" , "Feeling of impending illness" , "General feeling of unease or illness" , "Uneasy feeling" , "Out-of-sorts feeling" .)