I’m back, returned in my little car (4)
I believe the answer is:
mini
'car' is the definition.
(Mini Cooper)
'i'm back returned in' is the wordplay.
'i'm' becomes 'im' ().
'back' says the letters should be written backwards.
'returned' is a reversal indicator.
'im' back-to-front is 'mi'.
'in' in reverse letter order is 'ni'.
'mi'+'ni'='MINI'
'my little' is the link.
This may not be right. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for mini that I've seen before include "Car designed by Issigonis" , "Baby" , "Small (of car, skirt, disk,bar or series)" , "Short skirt - small car" , "Little - car" .)