Sudden pain, touching a knife (5)
I believe the answer is:
panga
'knife' is the definition.
(I know that panga is a type of knife)
'sudden pain touching a' is the wordplay.
I cannot really see how this works, but
'pain' could be 'pang' (pang is a kind of pain) and 'pang' is located in the answer.
'a' is found in the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for panga that I've seen before include "Deal successfully (with)" , "Heavy knife of East Africa" , "Heavy African knife" , "African machete-like tool" .)