"Not your day"
A: My train was delayed, my phone battery is dead and now I'm late.
B: Not your day is it?
Today is really not my day, my car broke down and now it's starting to rain.
A: I'm afraid it's not Lisa's day today. She got dumped by her boyfriend and now she has a cold too.
B: Poor Lisa...
What does "Not your day mean" mean?
We say 'not your day' to somebody who is having a bad day or lots of bad luck.
We often use it when many unlucky or bad things happen in a single day.
We can also use it with 'her, my, his or a name', for example 'not her day, not my day, not his day, not Helen's day'
It isn't actually about days!