Green’s Dictionary of Slang

(orig. US black) apprehensive, worried.

1957		R. Prather Always Leave ’Em Dying 128: I damn well wasn’t going to get all creeped up — the way everybody was supposed to — by the clever props.
1983		R. Price Breaks 91: I felt so creeped I broke from the catatonic clinch.
2000		(con. 1940s–60s) Décharné Straight from the Fridge Dad 2: All creeped up Scared, apprehensive, frightened.