Pregnant Nikki Bella Shows Off 'Much Bigger' Baby Bump: 'I Feel Like I'm Gonna Tear This Dress'

The second trimester looks good on Nikki Bella!

In a series of Instagram Story videos over the weekend, the former WWE star and first-time mom-to-be showed off her growing belly and talked about how much her body has changed over the course of just a few days.

“Getting ready because it’s gonna be Mama’s night out,” Nikki, 36, said in the clips (posted Sunday but labeled “Last night vibes”), panning her phone camera up and down to show her bump on display in a fitted black ensemble.

“I can’t believe I fit into this dress; this was a struggle right now. But I did, even though my boobs are so big it’s causing big gaps,” she continued, pulling gently on the portions near her shoulders to illustrate her point. “I feel like I’m gonna tear this dress but it looks good, right?”

“My bump has gotten so much bigger, literally, since Thursday. Look how cute,” Nikki said. “All right, I’m going with it. I’m gonna do it.”

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RELATED: Pregnant Twins Nikki and Brie Bella to Be Inducted Into WWE Hall of Fame

The Total Bellas star, who is expecting her first child with fiancé Artem Chigvintsev, recently shared that she was 16 weeks along in her pregnancy.

The previous week, she showed off her growing baby bump on her Instagram Story and gave her followers an update on how the pregnancy was going thus far.

“Thursday I turned 15 weeks. I should say we — I feel like I leave Artem out of this a lot,” Nikki told the camera. “We turned 15 weeks. Look at that, my baby. It’s always so hard to do this in a selfie video and I’m trying to take selfies in the mirror and it all gets really hard.”

“But I am very excited,” she added. “I’ve been feeling so much better. Definitely beginning of the week, I definitely was run down and starting to feel sick again, but I got an IV and I have to say, prescribed by my doctors so if you guys do IVs and your pregnant, go through your doctor first. It really helped me a lot.”

RELATED VIDEO: Brie and Nikki Bella Are Both Pregnant — and Due Less Than Two Weeks Apart

Last month, Nikki and her twin sister Brie revealed to PEOPLE that they are both pregnant and due less than two weeks from each other — which came as a “shock” to both of them.

“Wait, twins being pregnant at the same time?” Brie, who’s expecting her second child with husband Daniel Bryan, told PEOPLE at the time. “People are going to think that’s a joke. We both are shocked. People are going to think we planned it, but you can’t really plan pregnancy!”

“[It was] a total surprise,” Nikki added. “It took even me a good week to come to terms with like, ‘Oh my gosh, I’m pregnant.’ I’m not ready for it.”

Nikki also shut down rumors that the sisters underwent in vitro fertilization to time their pregnancies together on purpose, saying on Wednesday’s episode of The Bellas Podcast, “We ain’t the scheming twins. You got the wrong girls here. They weren’t even planned pregnancies, let alone at the same time.”