The very first song Blake Shelton ever wrote was inspired by a girl. (And call waiting, but mostly a girl.)

Shelton penned his first song one night as a teenager, after finding out a girl he had a major crush on had a thing for another guy named "Bird." Fans can find the notebook that contains the song at the now-star's just-opened exhibit at the Country Music Hall of Fame and Museum. Of all the things on display, he says he's most surprised that he found this old notebook.

The story goes that young Blake was on the phone with the girl, whom he refused to name on account of his publicist standing nearby and the fear that it'd turn into yet another tabloid frenzy. He did name the guy, however.

"She said, ‘I’m getting a call,'" the singer shares after explaining how call waiting works. "She said, ‘It’s Bird, oh my God I think he’s gonna ask me to the prom!'"

“I couldn’t believe it. I thought she liked me. Like, ‘That was the only reason I was even on the phone with you!'" he recalls.

After Shelton hung up, he picked up his guitar and wrote "That Girl Made a Fool Out of Me." You won't find it on an album, as the 39-year-old admits it's terrible and relies on the only four guitar chords he knew at the time. You will find the lyrics at the Country Hall of Fame, alongside his chair from The Voice, memorable outfits and awards, his knife collection and other artifacts from his life and career. The exhibit is open until November.

See Pics From Blake Shelton's Country Hall of Fame Exhibit