Melissa Schima was a nurse working in the psychiatric unit of the Saint John Regional Hospital on the evening of Feb. 14, 2012.
She told a five-person jury that Serena Perry had been in a good mood, laughing, joking and dancing around earlier that evening.
Schima saw Perry, whose cause of death has not been explained, leaving the unit at one point with other patients. Around 10:30 p.m. another nurse said Perry had not returned.
When Schima asked two patients if they knew where Perry was, one said that he had been with her in the amphitheatre, but she was "acting funny" and he left her there.
Nurse Paula Murphy told the inquest that the male patient said Perry had been acting erratic and talking about meeting God.
Schima and Murphy said they used the elevator near the psychiatric unit to travel to the first floor to get to the amphitheatre. On Monday, the hospital's manager of security services said that elevator was supposed to be turned off after 9 p.m.
Schima said, once she got to the amphitheatre, it didn't take any effort to open the door which was supposed to be locked.
Schima said they turned on the lights and saw Perry on the floor at the bottom of the amphitheatre. Perry's eyes were open and they thought she was looking at them, she said.
They called to her and as they walked down the steps and noticed that Perry was pale and had a housecoat around her neck.
Murphy left to call a Code Blue, an alert indicating there is a patient in need of immediate resuscitation.
Schima said she grabbed the housecoat and removed it, adding that it was not tight.
"The housecoat was not tight enough in my mind to have choked her," she said.
Both Shima and Murphy told the inquest that there were no knots in the housecoat and it looked like a smooth scarf around Perry's neck.
Schima could not find a pulse and started chest compressions. Other staff arrived to continue CPR but were unable to revive Perry, Schima said.
Several members of Perry's family left the courtroom in tears as Schima described the efforts to resuscitate the 22-year-old woman from Hampton.
Police have said a forensic pathology exam could not confirm the cause of Perry's death.
A suspect was arrested in connection with Perry's death a month after her body was found, but no charges were laid.
The jury also heard Tuesday from coroner Walt McKinney, who responded to the hospital just after midnight on Feb. 15, 2012.
McKinney said he learned from Perry's doctor that Perry did not have suicidal tendencies, and he ordered an autopsy because of her young age and the sudden nature of her death.
Outside the coroner's court, Rose Perry said she was glad that the inquest was told that her daughter was not suicidal.
She said she's encouraged by the fact the five-member jury has also been asking questions.
Two security guards testified they had done rounds on the night that Perry died and both had checked the doors to the amphitheatre where her body was found. They say each time they checked, the doors were locked and there was no indication anyone was inside.
Both said they knew that while the doors were locked, they could be opened with a hard pull.
On Monday, the inquest was told that the amphitheatre doors now have new locks and an alarm system.
About 50 witnesses are expected to be called during the three weeks set aside for the inquest.
Note to readers: This is a corrected story. An earlier version said the coroner testified last week.