Even though Kylie Jenner admits her body has "bounced back super fast" since welcoming her daughter, she's still struggled with post-baby body insecurities

Kylie Jenner’s body has gone through some changes since giving birth to daughter Stormi.

On Friday, while answering some fan questions with her best friend Jordyn Woods, the 20-year-old mom opened up about how even though her body has “bounced back super fast” since welcoming her daughter in February, she’s still struggled with her share of post-baby body insecurities.

“I feel like people think that I bounced back super fast, which I guess I did,” the Keeping Up with the Kardashians star remarked in a new video posted on her YouTube page, before adding that “people can get the wrong idea on Instagram sometimes.”

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Firing off a list of the most significant ways her body has changed, Jenner remarked, “My boobs are defiantly three times the size, which bothers me. I have stretch marks on my boobs. My stomach isn’t the same, my waist isn’t the same, my butt’s bigger, my thighs [are] bigger.”

“And honestly, I’m finding I have to change my style a little because nothing in my closet fits me from before,” she continued.

After previously announcing in the video that she had “planned my first workout on Monday,” the Kylie Cosmetics mogul added, “I really want to get my core back.”

“I feel like I have fake abs now, it’s just like, genetics. But I want real abs. I know I can have a super fit body. And just for my health — I want to do this. I want to feel good,” she explained.

Kylie Jenner and daughter Stormi
| Credit: Kylie Jenner/Instagram

But even though watching her body “go through such a change” at her age was “physically, mentally, and emotionally a challenge,” Jenner added that it was “also a beautiful thing.”

“It was such a great pregnancy and birth. And I’m so happy. I would have done the same thing over again,” Jenner said.

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The star gave fans a first glimpse at her post-baby transformation just seven weeks after giving birth to her daughter, posting a quick video on Snapchat of herself wearing a lifted-up black hoodie that exposed her stomach.

About one month later, Jenner was already back in a bikini — and since then she’s often showed off her toned post-baby physique on social media.

Kylie Jenner
| Credit: Kylie Jenner/Instagram

In March, Jenner revealed that she gained a total of 40 lbs. during pregnancy in a now-deleted tweet during a Q&A session with fans and followers.

Sources previously told PEOPLE that Jenner is determined to get back into pre-pregnancy shape because she wants to be a “really hot young mom.”

“Kylie is already starting to work out,” an insider said. “She’s focusing on getting her body back and also getting back to a comfortable weight aside from caring for Stormi,” adding that she “wasn’t the most comfortable while pregnant.”