Selena Gomez was expected to make her triumphant return to the stage during Sunday night's 2017 American Music Awards with a performance of "Wolves." However, the night didn't exactly go as many expected.

While the 25-year-old singer shared video teasers on Instagram in the days leading up to the event, which featured her singing live and sounding stunning, she seemingly chose to lip-sync her performance on Sunday night and many viewers called her out for possibly doing so on social media.

Since the show, Gomez has remained silent about the lip-syncing controversy but rumors continue to swirl online in regards to the singer's alleged decision to lip sync, some of which suggest a panic attack may have caused her to be unable to sing. That said, there may not be a whole lot of truth to the rumors.

“Selena didn’t have a full blown anxiety attack, but she did feel sick with nerves, and she was noticeably anxious before going on stage,” a source close to the singer told Hollywood Life on Nov. 20. “Selena always puts herself under so much pressure to give the best performance possible, and after all the incredible challenges of the past year, she just felt overwhelmed. But, Selena is such a professional, and she never wants to let her fans down, so she went out on stage and gave it her all.”

Prior to her performance, Gomez walked the red carpet solo as her boyfriend, Justin Bieber, skipped the event. While many fans were hoping to see the couple together, they reportedly felt it was best to keep their relationship out of the spotlight on Gomez's big night.

Continuing on, the Hollywood Life source slammed many people who have taken aim at Gomez after she allegedly lip-synched during her performance on Sunday night.

“Anyone criticizing her performance needs to check themselves unless you’re in Selena’s shoes it’s impossible to understand how stressful it can be to perform, especially after a whole year off,” the source continued. “Selena’s amazing, so strong and awesome—she deserves everyone’s support and love, not snarky comments and criticism.”

As for Selena Gomez and Justin Bieber, they appear to be going strong after confirming their relationship with a kiss in Los Angeles last week.