Source: Jessica Simpson Is "Not Pregnant"

Credit: Jordan Strauss/

Jessica Simpson is going to become a bride -- but not a mom, at least not yet!

A source close to the newly engaged singer tells, "She's not pregnant."

Simpson, 30, provoked fresh speculation about a potential baby during a Monday appearance on CBS' The Early Show.

Talking to CBS' Harry Smith about catching the flu, she admitted to throwing up moments earlier. "I've had better mornings, I have to admit...I won't let you smell my breath."

Explains the insider: "She was just sick."

Promoting her new Christmas album, Simpson, her parents and brand-new fiance Eric Johnson are spending their first Thanksgiving in NYC.

She told Smith about being "shocked" by Johnson's Nov. 11 proposal. "I didn't even try the ring on until 5 minutes in," she explained of the $150,000 bauble. "I just sat there and cried with [Eric]."

On Thursday, the engaged couple celebrated their engagement with about 50 friends and family and her parents' California home. "They were very happy," a Simpson pal told Us,