Pain caused by a double portion of sausage (6)
I believe the answer is:
twinge
'pain' is the definition.
(I know that twinge is a type of pain)
'a double portion of sausage' is the wordplay.
'a double' becomes 'twin' (twin can mean someone's double).
'portion of sausage' becomes 'ge' (I can't explain this - if you can you should give a lot more credence to this answer).
'twin'+'ge'='TWINGE'
'caused by' is the link.
Can you help me to learn more?
(Other definitions for twinge that I've seen before include "Sharp localised pain" , "Sudden stab of pain" , "Emotional pang" , "A slight stab of pain" , "A slight jab of pain (6)" .)