Fiddle operating, I may have a flutter (6,3)
I believe the answer is:
orange tip
'i may have a flutter' is the definition.
(type of butterfly - butterflies flutter around)
'fiddle operating' is the wordplay.
'fiddle' indicates an anagram.
'operating' with letters rearranged gives 'ORANGE-TIP'.
(Other definitions for orange tip that I've seen before include "Butterfly" , "Fluttery type" , "One may be studied by a lepidopterist" , "Flighty type" .)