After welcoming her first child, son Noah, on Sept. 27 with husband Brian Austin Green, Megan Fox is back at work -- and pulling double shifts!

The actress, 26, showed off her amazing post-baby bod at the Los Angeles premiere of This Is 40 at Grauman's Chinese Theater in Hollywood on Wednesday, Dec. 12. The new mom showed off her flat tummy in a long-sleeved, red Roland Mouret dress, Christian Louboutin heels, Jennifer Meyer jewelry and carried a Bottega Veneta clutch on the carpet.

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And bright and early the next morning -- 5:30 a.m. West Coast time! -- Fox looked as gorgeous as ever to present the 70th annual Golden Globe Awards nominations with Ed Helms and Jessica Alba at The Beverly Hilton Hotel in Beverly Hills. Wearing a floral, green-and-white Giambattista Valli dress, the hot mama flaunted a little more skin in the short, sleeveless design.

In an interview with Access Hollywood on Dec. 10, the This Is 40 star opened up about her labor experience for the first time ever -- and she was very honest!

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"I was screaming for an epidural when Brian was driving me to the hospital because my water broke on its own," the actress recalled. "It was level orange alert pain."

"It hurts so bad. It was so intense," she admitted. "And I thought I was gonna be really tough and make it, I was gonna labor to like 8 cm . . . but the first contraction that I got was horrific!"

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But she couldn't be happier as a new mommy.

"The whole thing has been overwhelming because I didn't realize you could love something so much, and I know people always say that but I love him so much it hurts," Fox told E! News, "and it's an interesting feeling to have because I never felt that before."

This article originally appeared on Megan Fox Flaunts Hot Post-Baby Bod in Two Sexy Outfits