TORONTO -- Alessia Cara insists she doesn't want to sound ungrateful, but coming to terms with stardom hasn't been easy.

The 21-year-old Canadian singer didn't anticipate her precipitous rise to success three years ago before it started -- not the Grammy Award for best new artist, nor the two Juno Awards. Not even the breakout radio popularity of "Scars to Your Beautiful," "Here" and "Stay" with Zedd seemed like a sure thing.

She also didn't expect the inexplicable feelings of sadness that began to wash over her life as fame took hold.

"There was a void I didn't know how to fill," she recalled ahead of the release of her single, "Growing Pains," on Friday.

"When you're going through something that is really beautiful, like my job, you almost feel guilty for feeling sad sometimes. You think, 'People are going to think I'm ungrateful if I talk about this,' so I just suppressed it, thinking that it would go away."

Instead, the feelings of sadness and loneliness persisted until Cara decided to seek professional support earlier this year.

"I go to therapy, which is really helpful," she said, emphasizing that she hasn't been diagnosed with depression.

"I'm still figuring it out, and right now I think they're just feelings of growing. If there's a name for it eventually that'll be something I can talk about freely, I'm sure, but right now I really just don't know."

Prioritizing herself wasn't always on the top of the list, Cara said, partly because she felt a responsibility to stand as a voice for others.

The singer, born Alessia Caracciolo, started out as a teen YouTuber in Brampton, Ont., a suburb outside Toronto, covering artists she admired, like Amy Winehouse and Lana Del Rey. Her work caught the attention of label executives at Def Jam and she was signed before her 18th birthday.

When her 2015 album "Know-It-All" arrived, she was quickly elevated as a pop artist with a strong message of empowerment and a relatable voice.

Her song "Scars to Your Beautiful," which addresses body image issues, became a talking point in the media, while her vocals on rapper Logic's "1-800-273-8255," named after the U.S. suicide hotline, put her in the centre of conversations about mental health.

Everything reached a crescendo when Cara stepped onto the Grammys stage in January to accept her award for best new artist -- an honour she dreamed of winning since she was a kid.

The moment was perfect, but the backlash was swift.

After the show, Cara's social media feeds were flooded with messages from people telling her she wasn't worthy. Some thought R&B singer SZA, a fellow nominee, was slighted and they wanted Cara to hear their opinions. It was enough for the singer to post on her Instagram account that she wasn't going to apologize to people to who want to "tell me how much I suck."

While the backlash has mostly settled down, recently a Wikipedia user altered the Grammy page to delete Cara's name from the category and substitute SZA as the winner.

"I'm not going to just be like, 'Oh it didn't faze me at all,' because it did," Cara said.

"When you have people from every angle sending you death threats for no reason, it's weird to handle. And then you start to believe it -- like did I actually take this (award) from another person? Do I not deserve this?"

It's been nearly six months since the Grammy incident, but for Cara there's a bigger question that she still struggles to answer: Why were some people happy to tear her down as the only female to win a major award on the Grammy telecast, she asks, while expressing outrage days earlier over the lack of women who were nominated?

"I just wish that people who were claiming to be feminists would help me out a bit and be supportive, instead of saying, 'Not that woman, this woman instead,"' she said.

"That doesn't feel like the essence of feminism to me."

Cara said coming through the experience taught her a few lessons about her own confidence.

"I deserved to be up there at the end of the day and that's something I never give myself credit for," Cara said.

"I never tell myself that I deserve it and I thought this time it was important for me to say I do."

The new pop single "Growing Pains" acknowledges Cara's evolving sense of self and the complexities that come along with personal growth. The song's lyrics are at once nervous and unsure, but eventually brim with optimism and hope.

She considers it "the perfect introduction" to her second album, a "conceptual" project due later this year that focuses on her personal experiences during this turbulent transition from a teenager into a young woman.

The album, titled "The Pains of Growing," started coming together as she toured North America last year. Some of the songs were written in the back of the bus, while others came together when she returned to Canada and was hanging out in her parents' Brampton basement.

"It's the first thing I've ever written totally on my own," Cara said.

Vocally it's also a solo project, with no guest singers or rappers slated to appear on the tracks, a decision that runs against the trend of many current Top 40 artists.

Cara said knowing her recent emotional turmoil will be slowly revealed in new songs is "weird" to think about, but she's found with music that "someone's pain is another's therapy," even when you're famous.

"Over time I've realized that just because you go through stuff it doesn't mean you're not grateful," she said.

"It just means you're human."