A salon owner tried to talk Britney Spears out of shaving her head, but the singer insisted and actually used a buzzer to do the job herself.
Salon owner Esther Tognozzi said Spears appeared at her shop late last week and announced she wanted all of her hair cut off.
Tognozzi said she refused to do it and tried to reason with the singer.
"Are you sure you're not having a bad day?" Tognozzi recalled asking Spears. "And tomorrow you'll feel differently about it?
"Why don't we wait a little bit?"
At that point, Tognozzi said, the singer grabbed some electric clippers and went to the back of the shop and began cutting her hair off.
All Tognozzi did was "even it out," the salon owner said.
Later, Spears was at a San Fernando Valley tattoo parlor, sporting her newly bald head.
Video on KABC-TV showed the newly shorn Spears with tiny tattoos on the back of her neck as she sat Friday night for a new tattoo -- a pair of red and pink lips.
"She just wanted something real small on her wrist, something dainty," Max Gott, the tattoo artist at Body and Soul in Sherman Oaks, told the TV station. "She got some cute little lips on her wrist."
Derrik Snell, who works at the tattoo parlor, said Spears showed up without notice and stayed for about 90 minutes as about 60 fans, photographers and gawkers gathered outside.
"She seemed fine," Snell said. "I didn't really notice [the hairdo] at first, she had a hood on when she showed up."
The appearance came the same day as reports on TV and Web sites that Spears, who has drawn criticism for her recent partying and sloppy behavior, had briefly checked into rehab.
Larry Rudolph, Spears' manager, couldn't be reached for comment.
Syndicated entertainment TV show "Extra" first reported that Spears had entered a treatment facility. Celebrity Web site TMZ.com then said the singer had entered a treatment center but had checked out one day later. Neither revealed their sources.
People magazine's Web site, citing "a source," said Spears had gone in and out of rehab, and identified the facility as Eric Clapton's Crossroads center in Antigua, in the Caribbean.
"Access Hollywood" then said the reports weren't true, but didn't cite a source.
A woman who answered the phone at Crossroads told The Associated Press that she couldn't confirm or deny anyone's presence at the facility.
Angelique Uram, a Spears fan who stood on the tattoo parlor's sidewalk for Friday night's spectacle, was aghast at the singer's new look.
"We could see her in the mirror, and her head is completely shaved," she told KABC. "It looks terrible."
Police arrived to control the crowd and helped Spears' bodyguards guide her into a waiting SUV, her head covered by a hooded sweatshirt.