The word “flabbergastled” doesn’t seem to exist, the closest word is “flabbergasted” Flabbergasted means the feeling or showing intense shock, surprise, or wonder : utterly astonished
to describe someone who's astounded or surprised for any reason,good or bad.
Explanation:
when you see your mom come back from the salon with bright green spiky hair and your jaw drops to the floor in total shock,your "flabbergasted".You are really really shocked-pretty much speechless.