Well then you probably picked it up from us, I'm pretty sure. The spasmodic overuse of "really" is a very recent thing here, but its DEEPLY entrenched. Its depressing to think its taken over in the land of...wherever you live.
At first it reminded me of ”ほんとですか?” as it is so often translated monotonously in 1980s anime dubs as "What's that? Is it really true!?". Then that charm wore of and its more grating than the previous decade's horrible linguistic defect; ending all of your sentences in "so..." as to imply a sort of off camera meaning or substance that was missing from the rest of the user's sentence (or paragraph, or day, or year, or life).
EDIT: Just saw another annoying used of "really?" only seconds after posting this:
Specifically called out in parenthesis, in a way you would do with nothing else I can think of. WTF? Its mass dementia, I tell you.
I feel like someone went back in time to hunt dinosaurs, stepped on a butterfly during the trip, and it instantly and permanently effected the English language...and I'm the only one who realizes it.