Became upset with small clothes (4)
I believe the answer is:
togs
'clothes' is the definition.
(togs can informally mean clothing)
'became upset with small' is the wordplay.
'became' becomes 'got' ('get' can be a synonym of 'become').
'upset' says the letters should be written backwards.
'with' is a charade indicator (letters next to each other).
'small' becomes 's' (abbreviation - e.g. clothes size).
'got' backwards is 'tog'.
'tog'+'s'='TOGS'
(Other definitions for togs that I've seen before include "Gear" , "Swimsuit" , "Clothes (sl.)" , "garment" , "Clothes (informal)" .)