I would guess this is some type of idiomatic expression in Gullah.
fludder-fedduh is probably flutter -feathers.
Feathers, I was able to confirm in a gullah dictionary. Flutter is just a logical guess. Someone who flutters their feathers could be a metaphor for a number of qualities..vain, sexy, ineffectual, proud, easily upset...etc... you need a clearer reference to know which it is.