Overtime laws

I’m not sure if it’s different everywhere but here’s my problems, at work we had an event where I had to work 11pm to 7am. I usually work mornings, so they said if I work the night shift and the morning shift, the morning 8 hours will count as overtime.

We didn’t have to but we would lose the money for the day all together if we took it off. well anyways, i worked the 16 hours 11pm to 3:30 pm the next day. with only a 30 minute break. Now they are saying the clocks reset and I don’t get paid overtime for the morning 8 hours just my normal rate. I thought if you worked over 8 hours in a 24 hour time period that it was counted as overtime if you are an hourly employee?