Sleep over but appearing upset for sure (2,5)
I believe the answer is:
no doubt
'for sure' is the definition.
(I've seen this in another clue)
'sleep over but appearing' is the wordplay.
'sleep' becomes 'nod' (I've seen this before).
'over' becomes 'o' (cricket abbreviation).
'appearing' indicates an anagram.
'but' is an anagram of 'ubt'.
'nod'+'o'+'ubt'='NO DOUBT'
'upset' is the link.
I am not very happy about this link. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for no doubt that I've seen before include "sign of agreement" , "Bound to, unquestionably" , "Almost certainly" , "Surely" , "To be sure" .)