PIC: Jessica Simpson Tweets About "Pregnancy Face," "Lip Injection Fairy"

Credit: Jon Kopaloff/FilmMagic; Twitter

Pregnant Jessica Simpson's belly isn't the only body part getting bigger!

"Woke up looking like the lip injection fairy visited me in the night!" the 31-year-old singer tweeted Sunday. "Is this how pregnancy face begins? Yikes!"

Though the Fashion Star mentor still has some time to go before welcoming her first child with fiance Eric Johnson, 32, Simpson recently tweeted that she's "looking forward to getting back into Daisy Duke shape with Mike Alexander. I forget what having a waistline feels like!"

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For now, Simpson is indulging in her favorite foods -- including buttered Pop Tarts. "I'm eating a lot of stuff that I ate in my childhood," she explained to Extra in mid-January. "Kraft Mac n' Cheese, Pop Tarts, Cap'n Crunch. Everything's filled with sugar."