Has anyone ever been attacked by a ladybug?

Yes, individuals report having been attacked by ladybugs [Coccinellidae]. Many such reports are in terms of Asian lady beetles/Japanese ladybugs [Harmonia axyridis]. Specifically, a ladybug that lands on human skin may or may not take a little bite. Researchers don't know exactly why that happens. The ladybug may be in search of minerals and salts. The bite may be a fear reaction on the order of the foul smelling, unattractive 'reflex bleeding' that ladybugs are known to emit when frightened or stressed.