TikTok star Nessa Barrett plays a hometown concert at the Fillmore

Four years ago, when Nessa Barrett was 16, she posted her first video on TikTok — a clip of her and some friends messing around in their South Jersey high school’s cafeteria. At the time, the Galloway native didn’t realize the loyal followers she was accruing on the platform would soon help her become a globally renowned pop star with millions of adoring fans.

Less than a year later, Barrett left for Los Angeles to pursue her music industry dreams.

She penned tracks like “I Hope Ur Miserable Until Ur Dead” and “Die First,” which brought a brutally honest gothic flair to the world of TikTok pop.

» READ MORE: It’s a Philly homecoming for Weyes Blood, who’s playing two shows at Union Transfer

At 8 p.m. Thursday, the musician and social media star will be in Philadelphia playing a homecoming show at the Fillmore. Her family, she said, will be in attendance.

She may see some high school friends there, as well.

Barrett — who plays guitar, piano, and violin — learned about composition and recording from her father, a rapper and producer, who let her experiment in his home studio. She was 4 when she wrote her first song.

Although Barrett has fond memories of making music and spending summer days down the Shore, she said her early years in South Jersey were often a challenge, particularly when it came to mental health.

“Nessa is the voice for sad girls everywhere,” said Michelina Beaumont, a fan who works with AmeriCorps helping Philadelphia-area teens prepare for college. The unvarnished way Barrett speaks about rage, love, and mental illness from a woman’s perspective is what resonates with her young fan base, Beaumont said.

The singer said the songs she’s working on with producer Evan Blair are her strongest to date and different from her past work. She’s hoping to court an older audience with her new lyrical approach, which she described as more “mature.”

Last month, Barrett released her newest single “BANG BANG!,” which will be included on a new EP she hopes to release this summer. It is an ominous, sultry track about romance gone wrong, replete with references to her struggle with borderline personality disorder, a common theme in her lyrics.

“I’ve been ashamed of it my entire life,” Barrett said. “I want to be the person I needed when I was younger.”

The early days of social media stardom posed some mental health concerns. She had experienced bullying before, but the haters who popped up in the comment section, alongside throngs of adoring fans, were hard to handle.

And she isn’t the only young TikToker struggling with this. Barrett’s best friend Cooper Noriega, another popular TikToker, died following an accidental overdose last year. Just days after his death, she released her track “Die First,” which she dedicated to Noriega. He got to listen to it before he passed and said it was his favorite track of hers.

Barrett doesn’t have TikTok or any social media apps on her phone anymore. Instead, her team posts on her behalf.

This, she said, has made it easier to focus on the loving fans she performs for every night.

Nessa Barrett performs with Isabel LaRosa at the Fillmore, on March 2, 8 p.m. Tickets are sold out.