Carrie Underwood is already looking forward to raising her first child with NHL husband Mike Fisher, but it looks like the country singer isn't only making changes in her personal life. Professionally, she's also hitting new heights.

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Something in the Water is the first single off Underwood's upcoming album Greatest Hits: Decade #1 and sold more than 124,000 copies during its first week, which began on Sept. 29.

According to a statement released on the singer's official site, the song has become the "best-selling first-week single of her career."

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"The sales figure also marks the best opening-week sales of any female country artist in 2014," continued the statement, adding that Something in the Water debuted on Billboard at no. 17 and hit 144 radio stations upon its first day on the airwaves.

Thrilled with the overwhelming success, Underwood took a moment to thank fans and country music radio on Twitter Tuesday for all the support.

Greatest Hits: Decade #1 will be available in stores Dec. 9, 2014.

Underwood and Fisher announced that they are expecting their first child back in September. They don't know the gender just yet and have elected not to share the due date with the public. The baby is expected sometime in Spring 2015.

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