Green’s Dictionary of Slang

wiffle-woffles n.

1. stomach-ache.

[UK]Hotten Dict. of Modern Sl. etc.
[UK]Sl. Dict.
[UK]Farmer & Henley Sl. and Its Analogues.

2. a state of depression.

[as sense 1].
[Scot]Dundee Courier 6 Apr. 6/3: Those fits of depression we call the ‘blues’ nowadays, they called wiffle-woffles.