LOS ANGELES — Michael Jackson's mother tearfully described finding out about her son's death and testified on Friday that she had expressed concerns about his comeback concert schedule to the promoters of the shows.

Katherine Jackson said she called Randy Phillips, the CEO of AEG Live, to voice her view that her son could have done 50 shows — but not if they were spaced closely together.

"He couldn't do every other night like AEG wanted him to do at first," she said.

Jackson also said she had called her son's manager, Tohme Tohme, to raise concerns about the "This Is It" schedule.

She didn't provide any additional details about the calls.

Jackson was expected to be the final witness called by her attorneys in the negligence lawsuit against AEG Live that has lasted 12 weeks. The defense case is scheduled to begin next week.

Her testimony was stopped in the early afternoon after her lawyer said she only had about three hours of sleep Thursday night and was tired.

The decision was made by Superior Court Judge Yvette Palazuelos after defense attorney Marvin S. Putnam asked Jackson several questions about her decision to file the case and she had difficulty understanding and recalling dates.

Palazuelos spoke with Jackson briefly before dismissing her until Monday.

Katherine Jackson has been a courtroom fixture during the civil trial, sitting in the front row as witnesses described her son's creativity and interactions with AEG Live executives.

The Jackson family matriarch sued AEG Live in 2010, claiming it failed to adequately investigate Dr. Conrad Murray, who was later convicted of involuntary manslaughter for giving the singer an overdose of anesthetic in 2009.

AEG denies it hired the doctor or bears any responsibility for the singer's death.

Katherine Jackson also said she had heard from her other children that Michael Jackson was abusing prescription medication, but she didn't know what to believe. She said she visited him in Las Vegas a few years ago to ask him about it.

"He promised, he kept saying, 'I'm OK,'" she told the jury. "Sometimes the mothers are the last to know."

She said she told her son, "I don't want to hear on the news that you're not here anymore."

She did not say when the meeting occurred.

Under questioning by Putnam, she said it had been difficult to see and hear unflattering descriptions of her son.

"It hurts to sit here and listen to all these things," Jackson said. "To listen to how sick my son was and nobody was trying to help him."

She said an email written by Paul Gongaware, a top AEG Live executive, that described her son as lazy was especially hurtful.

"My son is not lazy. You don't get to be the biggest," she said, pausing, "by being lazy."

She broke down as she described the day her son died and learning the news from another of her son's managers, Frank Dileo.

"I just started screaming," she said, crying and clutching a tissue in one of her hands.

Katherine Jackson said she had never met Murray before her son's death. She said she saw him pacing at the hospital and had to inquire who he was.

"My son needed another doctor, not Dr. Murray," she said.

The former cardiologist was convicted in 2011 and remains jailed.

Putnam asked Katherine Jackson about her decision to sue AEG Live. She said she didn't discuss it with her children or her grandchildren before filing the lawsuit.

"This was your decision alone," Putnam said.

She said it was.