"Mood Swings" was written by Tove Styrke, Christoph Andersson, Jenna Andrews, Noah Conrad, Rollo, and Sorana Pacurar.

In an interview for The Line of Best Fit, she explained, "I loved the vibe and could totally envision exactly what it was going to be when it's finished.

[4] In an interview for Wonderland, Styrke described the song as a "product of COVID" as it was made during several Zoom sessions.

"[8] Writing for Paper, Shaad D'Souza wrote positively of the single, "Tove has returned with this delightful, frothy, chaotic girl anthem.

"[9] "Mood Swings" debuted and peaked at number 62 on the Sverigetopplistan singles chart on 25 June 2021.