Eyelid problem, sore, that you experienced initially (4)
I believe the answer is:
stye
'eyelid problem' is the definition.
(I've seen this before)
'sore that you experienced initially' is the wordplay.
'initially' says to take the initial letters.
The initial letters of 'sore that you experienced' is 'STYE'.
(Other definitions for stye that I've seen before include "producing eyesore" , "Climb" , "swelling by organ" , "Animal pen" , "Ocular inflammation" .)