Ahmad Elatab / Splash News 1 / 4
Ahmad Elatab / Splash News 1 / 4

She's pregnant with a food baby!

Alyson Hannigan was the subject of pregnancy speculation over the weekend -- but it's a false alarm!

On Friday, the "How I Met Your Mother" actress, 37, was photographed hitting the Malibu Chili Cook-Off and carnival with husband Alexis Denisof and Satyana, their 2-year-old daughter. Wearing a loose-fitting top, Hannigan seemed to be sporting a noticeable baby bump.

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"NO, I'm not pregnant!" Hannigan Tweeted Sunday. "I just ate too much carnival food, that time of the month, hurt my back & couldn't suck my gut in, and need to do cardio!"

PHOTOS: Check out an adorable snapshot of Hannigan, her hubby and Satyana

She added of her less-than-flattering look: "And I'm NEVER gonna wear that shirt again!!!"

The good-natured star wasn't even annoyed at the assumptions, either.

 "I do LOOK pregnant in that photo!" she admitted.

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Plus, she had a great time at the Malibu carnival -- where her little girl Satyana won a goldfish.

"The carnival was really fun! And Sati won a goldfish on her 2nd try! Put my ping pong throwing skills to shame."