Ke$ha -- Bragged About Writing 'Die Young' Lyrics BEFORE Newtown Shooting

Ke$ha is either lying now ... or was lying then ... 'cause weeks before she said she was "forced" to sing the lyrics to "Die Young," she BRAGGED about penning the song during a radio interview.

The singer appeared on 95.5 WPLJ in New York back in November -- weeks before the Newtown massacre -- and took full credit for writing the song, saying:

"I definitely make sure that every word rings true to me because I would never want to misrepresent myself to millions of people around the world ... I wrote and rewrote and rewrote that song ten times."

Shocking, considering Ke$ha completely contradicted herself on Twitter yesterday after several radio stations around the country stopped playing the song in light of the Newtown tragedy. Ke$ha had written, "I did NOT want to sing those lyrics and I was FORCED TO."

The lyrics to "Die Young" include the line: "Let's make the most of the night like we're gonna die young. We're gonna die young. We're gonna die young."

So, what's the truth? We reached out to Ke$ha -- but haven't heard back.