Carrie Underwood probably won't be hearing the pitter-patter of little feet any time in her near future. She's got her hands full right now with her ultra-successful career, but she has admittedly thought about being a mom ... once life calms down a bit.

"One day, I'm absolutely fine and happy and start legitimately thinking about the idea of having kids, and the other day, I'm thinking, 'Oh gosh, no, no, what?' I can barely keep my own schedule straight," Carrie tells "Right now in my life, I'm smart enough to know that I'm a selfish person, and I can be, and that's OK. There's nothing wrong with that. At least I recognize it. That's a big step. It's like moving away from home. It's really scary until you do it and then you figure it out."

Since marrying pro hockey player Mike Fisher in 2010, she's been navigating deeper personal relationship waters, as well. Though she and her hubby are often apart for long stretches of time for their respective careers, Carrie recently told ABC's "Nightline" she has no trust issues when it comes to her husband's fidelity -- which is a definite change from her previous relationships.

"I know he loves me and I know he loves God. And he wouldn't do that to either one of us," she insists. "Every guy I've ever dated before Mike, somewhere in the back of my head, I would always have trust issues. With Mike, it never crosses my mind."

Carrie's new CD, Blown Away, which hits stores May 1, features a tune that speaks to that kind of longtime loyalty and devotion. "Forever Changed" is about a woman who is married with children and is approaching the end of her life. It's also one song that fans will likely never hear Carrie sing in public, because it just reminds her too much of losing her own grandmother.

"I get emotional even talking about this song," she admits. "It's just beautiful. It becomes very real ... and I remember my grandmother at the end of her life, looking at my dad and thinking that that was my grandfather. I can never sing this song on stage in front of people. I could barely get through it in the studio."

Blown Away will be released on Tuesday (May 1). Pre-order the album here.

Watch Carrie's 'Good Girl' Video