Pretend princess Antoinette Millard, who had claimed to be a Saudi royal, was locked up in the real Rikers Island Wednesday after prosecutors revealed she's been posing as doctor and a lawyer while spending royal sums she doesn't have on jewelry again.

Millard, 42, went on her latest spending spree while she was supposed to be locked up at a psychiatric hospital in Florida.

Millard's lawyer denied the allegations of wild spending, and said his client was simply engaged in "shopping therapy."

"This is a big misunderstanding," lawyer John Arlia told Manhattan Supreme Court Judge Renee White.

Millard, a shopaholic who once said she'd tried to commit "suicide by spending," pleaded guilty to grand larceny and insurance fraud last year on charges she stole hundreds of thousands of dollars by failing to pay for pricey jewelry.

She also admitted that she tried to collect a $262,000 insurance claim by saying her "family jewels" were stolen.

Under the terms of her plea deal, she was sentenced to a year in a New York psychiatric hospital last September, but unbeknownst to the judge was transferred to another hospital in Jacksonville, Fla., this past January.

Arlia said that as part of his client's treatment, she was allowed to go shopping with an escort.

"They took her to buy items with a credit card" to show her how to spend responsibly, Arlia said.

White said she'd ordered Millard to go for treatment -- not "shopping at Fortunoff's." She ordered her held without bail pending a hearing next week.