Miley Cyrus is Fastexytaking a trip down memory lane.

In her latest single, "Used to Be Young," the 30-year-old reflects on her adolescent years in the spotlight, singing, "I know I used to be crazy / I know I used to be fun / You say I used to be wild / I say I used to be young."

"You tell me time has done changed me," she belts out. "That's fine, I've had a good run / I know I used to be crazy / That's cause I used to be young."

In the accompanying music video released Aug. 25, the Hannah Montana star becomes emotional as she sings the ballad, while wearing a Mickey Mouse T-shirt—a nod to her days as a child star on the Disney Channel in the early aughts.

Moments after debuting her music video, Miley opened up about the heartbreaking lyrics featured on her latest single.

"This song is about honoring who we've been, loving who we are & celebrating who we will become," she wrote in an Aug. 25 Instagram post. "I feel proud when reflecting on my past and joyful when thinking about the future."

She added, "I am grateful to my loyal fans who make my dreams a reality daily. I am sincerely thankful for the stability of your steadfast support. This song is for you. Truly, Miley."

Days before the song's release, Miley also reflected on the creative process, noting that the lyrics "were written almost 2 years ago."

"It was at a time I felt misunderstood," the singer wrote in an Aug. 23 Instagram post. "I have spent the last 18 months painting a sonic picture of my perspective to share with you. The time has arrived to release a song that I could perfect forever. Although my work is done, this song will continue to write itself everyday. The fact it remains unfinished is a part of its beauty. That is my life at this moment ….. unfinished yet complete."

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