Two days after finding out she was pregnant,Brie Bellafound out sisterNikki Bellawas also pregnant — but her first reaction wasn’t at all what she expected.

In this week’s issue of PEOPLE, theTotalBellasstar, 36, explains why she wasn’t too thrilled at first about Nikki’s pregnancy — and why she didn’t talk to her sister for a week.

“Oh my gosh, this is a nightmare,” Brie, who shares 2-year-old daughter Birdie with husband and pro wrestler Daniel Bryan, says of her first reaction to Nikki’s pregnancy news.

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Brie Bella and Nikki Bella.James White

Brie and Nikki Bella

“Then I think really quickly, I was like, ‘Wait a second, [what about] what we talked about yesterday?’ Then, wait, twins being pregnant at the same time? People are going to think that’s a joke,” Brie continues. “People are going to think we planned it, but you can’t really plan pregnancy. It was just too much and to think I was also pregnant and my hormones are going crazy. I think that’s why that came out.”

“We both had to digest,” Nikki, who got engaged to formerDancing with the StarspartnerArtem Chigvintsevin November, says of her and Brie finding out about the pregnancies.

Nikki and Brie Bella.James White

Brie and Nikki Bella

On Wednesday, Nikki and Brie exclusively revealed to PEOPLE thatthey are (both!) pregnant— and due only a week and a half apart.

Because Nikki admits her pregnancy was a “total surprise,” she says it took her “a bit” to accept.

“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,’ ” she says. “My sister was right, because our little debates would always be, ‘Well, I’m gonna wait until I’m ready for it.’ Brie’s like, ‘You’re never ready for it.’ ”

But, nevertheless, Nikki is happier than ever.

“Even though I feel really sick, I can’t believe I’m going to be a mom soon,” she says. “I’m going to have this person to take care of for the rest of their life and help them do the right things and just show them the way of the world. That’s amazing!”

Total Bellasreturns this spring onE!.

For more from Nikki and Brie Bella, pick up this week’s issue ofPEOPLE, on newsstands Friday

source: people.com