A few weeks ago I woke up late and came very close to being late to work. I had woken up to my alarms, but had delayed getting out of bed to the point that I had fallen back to sleep. I woke up again not to my own alarm but to my roommate's. After peeking at the clock I jumped out of bed and rushed to ready myself for work in order to leave on time.
Talking to my roommate, she said that she had thought that it was weird that she'd set her alarm for 7:30 am when normally she would get up at 8 am, but when she had been setting her alarm the night before she had felt that she needed to set her alarm half an hour earlier than normal.