Teresa Giudice was shocked to discover last Thursday she will be checking into a federal prison Jan. 5 to serve 15 months on conspiracy and bankruptcy fraud charges.

That's what the "Real Housewives of New Jersey" star told Andy Cohen in an interview following her sentencing on "Watch What Happens Live" that aired last night on Bravo.

"I was so nervous [Thursday] that I was shaking," said Giudice. "My nerves were pulling. At one point I couldn't even move my fingers. Like, they were like stuck," she said.

She added that the sentencing "was very unexpected," and that she had experienced "sleepless nights."

Giudice appeared on the show with her husband, Giuseppe (AKA Joe), who will serve his 41-month sentence after Teresa is released, so as not to leave the couple's four daughters without a parent. The pair -- castigated by the judge for failing to disclose numerous assets on their returns -- were also ordered to pay $414,000 in restitution.

TMZ reported yesterday that the Giudices were paid a total of $325,000 to appear with Cohen on his show. A spokesman for Bravo said the amount "is completely inaccurate," but refused to say what they were paid.

Asked by Cohen if she was in denial, Giudice said, "I do need to read things before I sign them," and "I'm a trustworthy person," who needs to learn not to take all statements at face value. She conceded that if she doesn't understand what she signs, she should ask a contract lawyer for help.

Giudice was near tears while recounting that her daughter Gia, 13, told her that she'd help take care of her three younger sisters, and that the experience would be good training for motherhood. "I was like, oh my God. It broke my heart when she said that," Giudice recounted.

Bravo said previously it will not discuss how the Giudices criminal problems might affect the ongoing show.