HOLLYWOOD, Calif. — Carmen Electra may be having second thoughts about walking down the aisle with fiance Rob Patterson.

The former "Baywatch" star is reportedly upset after discovering that the engagement ring she's been flaunting was purchased online. Sources say Patterson purchased the black-diamond ring from the Web site mysolitaire.com for the price tag of $1,650.

"She seems really embarrassed," a source reveals in the latest issue of Life & Style Weekly magazine. "I think the ring is a real deal breaker. She thought she'd be getting this giant rock. Instead, Rob bought it online for a bargain price!"

The 37-year-old Patterson, a guitarist for rock band Korn, proposed last month while the couple was in Las Vegas celebrating Electra's 36th birthday. They have been dating for less than a year.

Should the engagement last to the big day, it will be Electra's third trip to the altar. She was previously married to Jane's Addiction and Red Hot Chili Peppers guitarist Dave Navarro, whom she wed in 2003. The couple officially divorced in 2007.

The former MTV "Singled Out" host was also briefly married to former NBA star Dennis Rodman.

However, insiders say the odds of Patterson and Electra eating wedding cake together are slim.

"Rob doesn't have a lot of money coming in," a source tells Life & Style, "and he's been driving around in Carmen's car while she's working. Carmen's starting to realize that Rob may not be able to hold up his end of the bargain."

"The less time they spend together, the longer the relationship will drag on, but it won't last," the insider adds. "She'll come to her senses."