Okay, seriously?! How did Kylie Jenner lose the baby weight so quickly?! The new mama's post-baby body is already looking better than ever, just about five weeks after giving birth to her first child, Stormi Webster. The 20-year-old took to Instagram to share a sexy mirror pic with BFF Jordyn Woods before attending Tristan Thompson's birthday bash on Saturday, March 10 — and her teeny waist is the only thing we can look at. Check out the video above to see the snap!

After months of hiding, the reality star is quickly making her return to social media. Saturday was a busy day for the Kardashian-Jenner clan, as they celebrated both Khloé Kardashian's baby shower and Tristan Thompson's 27th birthday — and Kylie made several appearances on both her and her family's Instagram accounts.

Clearly, Ky is super proud of her weight loss transformation, captioning her sexy snap with Jordyn, "Back at it again." According to an insider, the young mom felt a lot of pressure to get her body back because she felt "unattractive and fat" during her pregnancy — which is why she basically went into hiding. "She called herself 'fat,' 'gross,' and 'disgusting' all the time," the source told Life & Style. "There was no way Kylie wanted to be seen in public. Now she feels like she’s got a lot to prove." She must be satisfied with her post-baby body now, and for good reason!

The makeup mogul is also slowly, but surely, sharing more pics of her firstborn. The proud mom can't help but gush about little Stormi, and she seems to be fully embracing motherhood. "She's been crying tears of joy. She can't believe she's a mom," another source divulged to In Touch. "This is the first of many babies for Kylie. Nobody would be surprised if she has another one next year!" How exciting!

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