"Right now I feel nauseous, I'm exhausted," the singer said Friday on her husband's Rollin' with Nick Cannon radio show on 92.3 NOW.
Carey, who is currently promoting her new Merry Christmas II You album, says she'll stop working once the holidays are over: "I guess after New Year's," she said.
The five-time Grammy Award-winning singer, 41, also says she's been "insulated" from the outside world since sharing their baby news with the world.
"I didn't even look and see who contacted me," she said.
When it comes to Christmas, Cannon, 30, said the couple always celebrate lavishly, and this year's festivities will be even "bigger" than before because the couple has "lots to celebrate" – a sentiment echoed by his wife.
"Yes, we do," said Carey. "We definitely, most certainly do."