Heidi Montag's mom Darlene is livid with her plastic surgery-obsessed daughter.

When Heidi underwent 10 plastic surgery procedures in one day, The Hills star kept those plans secret from friends, and even her family. For very good reason.

Now, nine weeks after her "dramatic transformation," which actually didn't change her as much as the first batch of surgeries she got, Montag's mom knows.

And Darlene Egelhoff is pissed.

"I still can't believe I'm 23 and mom is reacting this way," Montag confessed to People. "I'm nervous to go home and face her. Especially with cameras rolling."

CYBORG: Heidi is more Barbie than human. [Photo: PacificCoastNewsOnline.com]

A source close to the family says Darlene is even more upset than when she brought home Spencer Pratt, or when she heard Heidi's terrible debut album.

"She is horrified and having a total breakdown," a source says of Heidi Montag's mother. "She lost it. She can't wait to confront Heidi when she goes home."

The Colorado resident will get her wish soon, as "Heidi is planning to head back to her small town of Crested Butte very soon," says a source close to the 'Tag.

Hills fans will get to see the drama play out next season on MTV hit, as cameras will catch every moment. Bet they paid for her 10-surgery bonanza, too.

Heidi Montag looked hotter ...