She entered the lift and was heading up to her workplace on the 12th storey at UE Square.
But as she got to the 10th storey, the lift suddenly rumbled and shook violently.
The next thing she knew, it plunged. It is believed to have plunged three storeys.
"It felt like I was on a roller coaster. I was scared to death," said the woman, who gave her name as Miss Yeo.
But the ordeal wasn't over.
Miss Yeo and the three other women trapped in the lift at the River Valley Road building were rescued only about 1½ hours later.
On Tuesday, Miss Yeo, 24, a financial analyst, recounted the incident which happened at about 8.40am on Monday.
One of the women in the lift had said she heard something snap before it fell.
She and the other two women immediately squatted and braced for impact.
Miss Yeo said: "But I was too scared and couldn't react. It felt like a very long drop. I thought I was going to die."
When the lift came to a stop after a few seconds, Miss Yeo immediately sounded the alarm for help.
Security personnel responded, telling them over the intercom that technicians were on their way.
"But we had no idea how long we were going to be trapped in the lift for," said Miss Yeo, who phoned her boyfriend and told him what happened.
"I was very scared. I was so afraid it would drop again."
After about 1½ hours, the lift started moving upwards.
"It wasn't the normal travelling speed of the lift. It felt like it was being pulled upwards," she said.
When technicians forced the door open at the 10th storey, Miss Yeo wasted no time rushing out of the lift, stumbling and tripping in the process.
She later found out from her boss that the lift had fallen almost three storeys. "I couldn't sleep that night as I kept thinking about what happened," she said.
"The next day, I had to ask a colleague to accompany me to take the lift - this time I took the one that had windows."
A spokesman for UE ServiceCorp, the property management of UE Square, said the lift maintenance contractor is investigating the cause of the incident.
"We would like to assure users that all safety features of our lifts are in place."
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