LOS ANGELES – Paris Hilton wailed after a judge sentenced her to 45 days in jail – with no weekend passes or special privileges – for driving with a suspended license a month after a cop warned her not to.

The 26-year-old hotel heiress was stunned and shaken when Judge Michael Sauer laid down the law and told her to report to the can by June 5.

“I don’t know what happened … I did what they said,” she complained in a quivering voice after making the sign of the cross and putting her folded hands to her mouth.

Then “The Simple Life” star broke down, sobbing loudly as her socialite mom Kathy Hilton hugged and comforted her in Metropolitan Court.

The leggy blonde, who wore a prim pinstripe navy jacket and white blouse, showed up 20 minutes late for the 1:30 hearing, powdering her nose on the way in. On the way out, she donned dark sunglasses to hide her tear-streaked eyes and runny makeup.

During the 2½-hour hearing, Hilton blamed misinformation from her “advisers” for her two forays behind the wheel while her license was suspended for an alcohol-related reckless driving conviction. That stemmed from a margarita-fueled drunken-driving arrest.

“I wasn’t allowed to drive for 30 days … and I follow the laws,” she said, summing up her incorrect understanding of the situation.

When a prosecutor asked if she read the license suspension notice that was mailed to her from the DMV, she replied, “I have people do that for me.”

The hotel heiress said she didn’t read her plea agreement either. “I just sign what people tell me to sign,” she said.

She looked genuinely confused when the prosecutor told her she “waived her rights” when she pleaded no contest to the booze-related driving charge in January.

Her publicist, Elliot Mintz, tried to take the fall, testifying that he told Hilton it was okay to drive after 30 days for “work-related” purposes. He claimed he was misinformed.

The prosecutor made his case. “We are asking that she be held to the same standard as everyone else who goes through this system,” Assistant City Attorney Dan Jeffries argued.

Sauer did not buy Hilton’s shaky claims that her advisers told her she was allowed to drive, especially after she got a written warning, which she signed, from a California Highway Patrol cop on Jan. 15.

The next month, on Feb. 27, she was stopped and cited when she drove her Bentley again – this time with the headlights off, even though it was 11 p.m.

“This is a case of what the defendant knew and when did she know it … What did the defendant know about her license?” Sauer asked before he brought the hammer down.

Noting the form she signed when she was pulled over in January, he said, “That exhibit is the smoking gun in this case. She carried this in her car for two months … In my opinion there is no doubt she knew her license was suspended.”

The judge blasted her publicist. “Mintz threw himself on his sword … His testimony was worthless,” the judge fumed. “I’m not sure she was mistakenly advised. She wanted to disregard everything that was said, and continue to drive.”

When Hilton saw the writing on the wall and sensed the judge’s mood, she tried pleading with him.

“I just want to say I’m sorry, and I didn’t do it purposely at all,” she said.

It didn’t work. The judge had one last crack. “She’s driving around with that in her car. I think she completely ignored that piece of paper … The defendant is to serve 45 days in jail.”

If she doesn’t report to the Century Regional Detention Facility in Lynwood, N.Y., by June 5, the judge ordered her sentence doubled to 90 days.

Prosecutors wanted to impound her car as punishment, but the judge refused.

“I think she probably has about five other cars,” the jurist said. Hilton’s mother glared at him, and he apologized for the “facetious” comment.

Hilton’s lawyer, Howard Weitzman, vowed to appeal.

“The sentence is inappropriate and borders on the ludicrous. The judge singled her out because of who she is. Shame on the system and shame on the city attorney,” the attorney griped.