Kelly Clarkson's Wednesday night (Aug. 19) concert crowd got quite the surprise: She let it slip that she is pregnant with her second child!

According to ETOnline, the 33-year-old former American Idol winner got emotional while singing "Piece By Piece," a song about Clarkson's relationship with her dad, and unexpectedly dropped the big news.

“I was totally not planning on announcing this, but ... I’m totally pregnant,” Clarkson told the crowd at Los Angeles' Staples Center, according to People. ”I’m having a really hard time.

"... That was not how I wanted to announce that ... I hate this song right now,” the singer continued. “My makeup artist is backstage hating me right now. I just don’t want you to think I’m on pills or drunk."

And if any fans didn't believe her the first time, after Clarkson finished the song, she explained that the moment really was unplanned -- she and husband Brandon Blackstock haven't even told their extended family yet!

"I’d like to apologize to my husband. That was not planned. I just didn’t want you to think I was crazy or something," Clarkson added. "Honestly, I’m just so hormonal today ... I haven’t vomited yet. That is a freakin’ win, y’all.”

Clarkson and Blackstock, who is Reba McEntire’s stepson, met at the 2012 Super Bowl, got engaged later that year and -- after canceling their original plans for a big wedding -- eloped, marrying in October of 2013 in front of a small group of close friends and family. That November, the couple announced that Clarkson was pregnant with their first child, daughter River Rose, who was born in June of 2014.

Fans following Clarkson closely won't be too surprised at the news of her new pregnancy: In June, she said that she was ready to start trying for a second baby after her tour. Her Piece By Piece Tour is scheduled to continue through mid-October, with a smattering of dates also scheduled in mid-November; see a full list of upcoming shows on her website.

See Kelly Clarkson's Yearbook Picture!

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