Acute annoyance or disappointment (7)
I believe the answer is:
chagrin
I believe this is a double definition.
'acute annoyance' is the first definition.
(chagrin is annoyance or irritation)
'disappointment' is the second definition.
(thesaurus)
(Other definitions for chagrin that I've seen before include "Shame at one's failure" , "Annoyance/shame at one's failure" , "Strong feeling of embarrassment" , "Frustration at having failed" , "Arching with annoyance and embarrassment" .)