He was extremely excited". Lee and Tamposi then left for Kygo and Watt to work on the production where they followed the melodies and message of the demo. According to Tamposi, the producers brought the song to life. The three songwriters would usually spend several months pitching their songs to different singers, but with "It Ain't Me" Gomez heard it about a month afterward and recorded it a few days later. Tamposi was called back for the vocal sessions with Gomez where they shared a similar emotional vision for "It Ain't Me", basing it on their own personal experiences. Recalling the sessions, Tamposi said she was impressed with Gomez's involvement and the ideas she came up with for the song. Music and lyrics An EDM, dance-pop, electropop and tropical house song, "It Ain't Me" is composed in the key of C Major and is set in the time signature of alla breve at a tempo of 100 beats per minute. Gomez's vocal range spans from the low note of G3 to the high note of E5, while the music follows the chord progression of Am–C–F–C–F–C–G. Later in the song, the piano plays in a chord progression of: Am–C–G–F–Am–C–G. The song carries a calm tone and a drop common in tropical house music, but is complemented by an equal measure of electronic and pop rock elements. The track starts with a folk-like acoustic guitar riff. It is followed immediately by Gomez singing the first verse in a husky tone. As the song develops, a steady bass and synthesizers are heard. The production is subtle and varied with finger snaps sometimes being louder than the kick drum, and the guitar riff and piano notes alternating in and out. In the chorus, Gomez is accompanied by background vocals that pertain to the sound of a choir. The chorus has a new melodic arrangement and a crescendo. It is ensued by chord-buoyed builds and drops comprising finger snaps and pan flute melodies. The same synthesizers from the verses are repeated with a sidechained piano in the background. In the drop Kygo introduces sidechained vocal chops of Gomez singing syllables and are accompanied by percussion instruments. "It Ain't Me" is a breakup song with a theme of nostalgia. The lyrics are about standing up for yourself in the face of a toxic relationship. Gomez narrates the regret of a previous relationship ruined by her former