German-born pop star Kim Petras used to sing about living in the lap of luxury. Her breakthrough song, 2017’s “I Don’t Want It at All,” was an infectious, “Material Girl”-like bop about the thrills of a well-heeled lifestyle — summers in the Hamptons, sprawling closets full of designer clothes — but one that was worlds away from Petras’ reality.

“I wrote all these songs about what I wanted my life to be, and really glamorized my life, while living on my futon and a shared apartment with four people,” says Petras, 26. “And now I feel like I’ve become a lot more confident.”

That confidence is apparent in Petras’ recent string of songs, which she’ll perform at The Fillmore on Saturday as part of her first headlining tour. The delicate pop number “Broken,” released in April, set the tone for Petras’ new era of music. It was a complete about-face from her previous single, the party starter “1, 2, 3 dayz up,” which featured electro-pop producer SOPHIE. The chance to vent about being heartbroken over an ex was therapeutic for Petras — but a feeling of guilt came along with it.

“A part of me felt a little bad for making sad songs because I feel so blessed,” says Petras, who moved to L.A. when she was 19. “It’s nice to tour, drop singles and make music as my job. I don’t take it for granted and I’m not sitting around going, ‘Aw, poor me,’ but that’s what I was going through personally.”

There are still plenty of fun-loving hits in the latest mix, including “Do Me,” which is, as Petras puts succinctly, “a song about being a ho!” and “Got My Number,” in which she shares a phone number and invites listeners to call her “for a good time.” (The number was actually real and belonged to her friend and collaborator Jesse Saint John.) So far she’s released all her work independently, managing to get more than 125 million streams online without a major label push.

For Petras, being authentic goes beyond wearing her heart on her sleeve and maintaining her creative freedom. She’s also an inspiration for the LGBTQ community. At 16, she made international headlines as the youngest person in the world to undergo sexual reassignment surgery. She makes a point to not let her identity overshadow her art, though she’s still a visible champion for the trans community.

“I want to be a role model for young trans kids,” says Petras, who was nominated this year for GLAAD’s Outstanding Music Artist award. “My whole teen life was dedicated to saying, ‘Look, I’m transgender, I’m a normal person.’ I always want to keep fighting for the LGBTQ community because that’s been my home.”

Meanwhile, Petras is updating her sound, but not how the music is supposed to feel.

“Pop music, to me, has always been an escape,” Petras says. “[My music] is supposed to take people out of their everyday problems and make them forget if they feel s---ty. But there are also a bunch of party bangers, and I hope that people just have fun.”