NASHVILLE, Tenn. — Police confirmed today that ex-NFL star Steve McNair's 20-year-old girlfriend killed him before turning the gun on herself.

They said they may never know what was going through Sahel Kazemi's mind when she shot McNair in his condominium early Saturday, but interviews with friends led detectives to conclude she was becoming increasingly distraught over events in her life, including financial problems. Police said she also suspected McNair was seeing another woman.

Police earlier had labeled McNair's death a homicide, but awaited further tests and investigation before saying for sure what happened.

At one point, Kazemi told an associate that her "personal life was all screwed up," Police Chief Ronal Serpas said. She had mounting debts and had been unable to sell her car. Her roommate was moving, which would have doubled her rent.

"We do know that she was clearly sending a message during the last five to seven days of her life that things were going bad quickly," Serpas said, though there was no indication she told anyone she planned to harm McNair.

Serpas said police believe McNair was asleep on a sofa when Kazemi shot him in the head. She then apparently shot him twice in the chest before shooting him again in the head and then shooting herself.

McNair, a quarterback for the Tennessee Titans most of his career, was shot at a condo he rented with another man. The gun was found underneath Kazemi.

Kazemi's family told reporters that the woman was so confident McNair was divorcing his wife of 12 years that she was preparing to sell her furniture and move in with him.

But associate Mike Mu, who has worked with McNair's charitable association for years, said McNair's wife, Mechelle McNair, "didn't know who this girl is." No records of divorce proceedings have surfaced.

Two days before the shooting, police stopped Kazemi driving the Escalade sport utility vehicle that McNair gave her for her birthday in May.

According to an arrest affidavit, Kazemi had bloodshot eyes and alcohol on her breath. She refused a breath test and told an officer "she was not drunk, she was high." She was charged with DUI. McNair was with her but not charged. He later made her bail.