Carrie Underwood on the End of American Idol: "It's Very Bittersweet"

Carrie Underwood had a lot to celebrate at last night's American Music Awards, including a gorgeous dress that she rocked on the red carpet, a killer performance of her song "Heartbeat," and a win for favorite country female artist.

But what was really on her mind? The impending end of American Idol, which gave the star her big break. "It’s very bittersweet for American Idol to no longer be on TV after this season. 15 seasons, 15 years is an incredible amount of time for any television show to be running that successfully. So I feel like they should all be so, so, so proud," she said. "And I of course am thankful for that show because I wouldn’t be standing here without it. It’ll be fun to see the last season, though. I think they’re going to go out with a bang. Again, it gave people like me a chance. It’s changed the music industry, changed the entertainment world, and I’m beyond grateful for it."

And as for her dazzling Elie Madi look at the event, the country star fell in love with it instantly. "I just work with incredible stylists who knew I would absolutely love this dress. I walked in and they were like, this is our favorite. So, I tried it on, and then I tried on a couple after and said, we don’t need to do anymore…we got it. I love that."

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Underwood's cape dress came complete with a long train that her team toted for her as she made her way around the venue. "People are respecting the train," she said. "They’re staying away from the train,."

—With reporting by Brandi Fowler