Nikki Bella Shares Details of the Sweet Moment She Knew Artem Chigvintsev Was an 'Amazing' Dad

"When you see them just let go and be so emotional while they're holding something you love so much is the best feeling ever," Nikki Bella tells PEOPLE

After welcoming her first son, Nikki Bella is feeling all the feels — and is blessed to have a supportive partner by her side.

In this week's issue of PEOPLE, the Total Bellas star — who welcomed her first child, Matteo Artemovich, with her fiancé, Dancing with the Stars pro Artem Chigvintsev, 38, on July 31 — is opening up about the first time she saw Chigvintsev hold their baby and what that moment meant to her.

"It made me so emotional," Nikki says of seeing Chigvintsev hold their son for the first time. "It's crazy because I'm already in love with this person. I've created a life with them and we're engaged."

She adds, "But in that moment I had fallen so much more in love with him because to see him be so emotional holding his son, and I could just see this caretaker form, like this man that's going to protect this little boy for the rest of his life. Just seeing the emotion in his face, it made me melt."

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Nikki Bella, Artem Chigvintsev, and Matteo. Brian Bowen Smith

"I was like, 'We need to plan our wedding. I need to lock this s--- in.' But it just melted me," she says. "I could just tell in that moment that he was going to be such an amazing father. You rarely see that side of men. So when you see them just let go and be so emotional while they're holding something you love so much is the best feeling ever. Huge turn on."

Bella, who got engaged to Chigvintsev during a trip to France in November 2019, says she's so "blessed" to have him by her side.

"I don't know how I would do all this without him," she says. "He's very attentive. He will wake up at any moment if I need a break. He'll hold Matteo, change diapers, anything I need. He never complains. He's always helpful."

"It's just really cute because there'll be times where I'm like, 'No. I need to swaddle him and have him sleep in the bassinet,' because Artem, he would have Matteo sleep on him all day and all night. He's so obsessed with it," she explains. "I have to tell him, 'You get your one, three hours a day because he just needs to be in the bassinet too.' He's been amazing. I have to say, he's more than what I expected. I didn't know what to expect because we both are first-timers. I was someone who so desperately wanted to be a mom and I knew he wanted to be a dad, but I don't think as soon as I did."

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The Bella Twins. Brian Bowen Smith

Originally due August 6, Nikki was on her way to get induced early (her doctors were worried about high blood pressure and offered the option of being induced one week prior), when her water broke in the doctor's office.

"Artem and I were so not prepared," she admits. "We barely had bags packed. I labored for 22 hours, and I pushed for two hours while wearing a mask because of COVID-19. It was 118 degrees in Phoenix, and our room wouldn't get colder than 76 degrees, so I was burning hot the whole time. I had two more rounds of pushing [to go] until my doctor said, 'You're going to have to have a c-section.' I said, 'No, he's coming out vaginally.' "

"I looked at Artem [who was allowed in the room with a mask], and I go, 'Put on the Lumineers!' And literally we 'Hey Ho'-ed and '-Ophelia'-ed Matteo into this world," the new mom adds. "I have never pushed so hard in my life. I almost tore off the handlebars!"

Watch the full episode of People Cover Story: The Bella Twins streaming now on PeopleTV.com, or download the PeopleTV app on your favorite device.

Twin sister Brie and husband Daniel Bryan welcomed their son Buddy Dessert on Aug. 1, a mere 22 hours later.

"I was trying to have a VBAC [a vaginal birth after a previous cesarean section] because I had an emergency c-section with Birdie, but I forgot I make stubborn babies, and they don't like to come out," says Brie. "When Matteo came on the 31st, I was like, 'No matter what, my baby is coming at 9 a.m. tomorrow.' We didn't know it was a boy yet."

"This experience was so different from my last — just to walk into a c-section and be completely alert," she adds. "When they pulled out Buddy, they put down the curtain, and my husband was like, 'Oh, I got a boy!' We were really overwhelmed with joy."