slaphappy
slap-hap-py
adjective
Dazed, giddy, or foolishly cheerful, often from a blow to the head.
"He was a bit slaphappy after the rugby match."
Thesaurus
Synonyms: harum-scarum, happy-go-lucky, carefree, freewheeling, devil-may-care, irresponsible, punch-drunk, silly, confused