A lot of pain, mostly difficult turning over? Here’s encouraging response (6)
I believe the answer is:
hurrah
'turning over? here's encouraging response' is the definition.
I can't judge whether this defines the answer.
'a lot of pain mostly difficult' is the wordplay.
'a lot of' means to remove the last letter (a lot of but not all of the word).
'pain' becomes 'hurt' (hurt is a kind of pain).
'mostly difficult' becomes 'rah' (I am not sure about this - if you are sure you should believe this answer much more).
'hurt' with its last letter taken away is 'hur'.
'hur'+'rah'='HURRAH'
Can you help me to learn more?
(Other definitions for hurrah that I've seen before include "Expression of joy (H, not Y)" , "Exclamation of approval or joy" , "Last ____, final act" , "Joyful exclamation" , "Cry of congratulation or celebration" .)