Following the August 1 announcement that Carrie Underwood would be taking Katy Perry’s seat as a judge on American Idol, the “Before He Cheats” singer, 41, confessed she had “a big problem.”

“I can’t lie. I just can’t. You can tell,” she said on Good Morning America. “Hopefully, I’ll be very honest, but very encouraging.”

While Carrie’s purported honesty may ruffle the feathers of some aspiring idols, she actually has a lot more to worry about with her new gig. “Carrie is excited, but now that it’s official, she’s stressed out and under a lot of pressure,” an insider exclusively tells Life & Style. “Though she isn’t admitting it, Carrie thinks she may have taken on too much.”

One of the biggest issues is that zany Katy, 39, left some pretty steep platform heels to fill. Case in point: Lamenting Carrie’s selection, a critic for The Daily Beast wrote that while Katy was “damn funny,” Carrie is “not exactly known for her huge personality.” Ouch.

“Haters claim Carrie will have a hard time living up to Katy, who was outrageous and a great mentor,” says the insider. “Carrie is desperate to prove she will not only thrive but can also bring in the ratings.”

Even Carrie’s husband of 14 years, Mike Fisher, is allegedly harboring doubts, though. Explains the insider: “He is a little concerned she may perform poorly under pressure.”

Carrie Underwood Will Be Far From Family on ‘American Idol’

Though Mike, 44, wants Carrie to succeed, the job itself is a source of contention for the couple, who are parents to Isaiah, 9, and Jacob, 5. The family is based in Franklin, Tennessee, and Mike and the children were already struggling with Carrie’s absence whenever she was gone for her Las Vegas residency, Reflection.

“Mike didn’t want her to do Idol initially, but she insisted, and the paycheck is substantial,” says the insider of the estimated $25M the country star will earn per season. “Mike is worried Carrie won’t be able to balance her life, commuting between Tennessee and L.A. It’s a huge adjustment, more than her residency in Las Vegas, which they never saw eye to eye on, either.”

With AI auditions having kicked off on August 12, Carrie is focusing on getting her bearings — and being a former contestant definitely helps. She’s also gotten a public show of support from host Ryan Seacrest, 49.

“Carrie will either rise to the occasion and shine brightly, like she’s usually done in the past, or she’ll sink under the enormous expectations,” says the insider. “She’s got her fingers crossed, and she’s praying a ton that this works out, but only time will tell.”