Bristol Palin Instagrammed a baby bump selfie. Credit: Courtesy of Bristol Palin/Instagram

Baby's first selfie! Pregnant with her second child, Bristol Palin is all about documenting her 2015 milestones on Instagram. Last week, the Wasilla, Alaska, native got to celebrate two major moments: Six years at her job, and her first baby bump selfie.

On July 13, Palin, 24, took a selfie in the dermatology office where she works as a medical assistant, showing off a hint of her still tiny baby bump. Wearing a white blouse and a long coat, Palin pouted her lips in the mirror photo. (Look closely: Her iPhone case features a photo of son Tripp, 6!)

Palin confirmed she was expecting in June, and has spent much of her time defending her pregnancy. "I know this has been, and will be, a huge disappointment to my family, to my close friends, and to many of you. But please respect Tripp's and my privacy during this time," Palin wrote in a blog post on June 25. "I do not want any lectures and I do not want any sympathy."

Her pregnancy news came mere weeks after she canceled her Memorial Day weekend wedding to Marine Dakota Meyer one week before she was due to walk down the aisle. Palin, the daughter of former Republican vice presidential nominee Sarah Palin, hasn't yet confirmed her baby’s paternity, but revealed last month that her pregnancy was indeed planned.

"Everyone knows I wanted more kids, to have a bigger family," Levi Johnston’s ex said. “Believing I was heading that way, I got ahead of myself. Things didn't go as planned, but life keeps going. Life moves on."

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