Green’s Dictionary of Slang

nerves, tension; thus get the woofits, to become tense, nervous; a hangover.

1918		J.M. Grider War Birds (1927) 96: Curtis says he is suffering from the Woofits, that dread disease that comes from overeating and underdrinking.
1932		J.L. Kuethe ‘Johns Hopkins Jargon’ in AS VII:5 338: woofits — ailment that comes with ‘the morning after the night before.’.