not someone's day

not (one's) day

A day that has been particularly stressful, difficult, disappointing, or filled with unfortunate events for one; not a good day. I can't believe I got locked out of the apartment. This is just not my day. I'm sorry, sweetie, I know you studied hard for that test. It just wasn't your day.
See also: not

not someone's day

used to convey that someone has suffered a day of successive misfortunes. informal
1997 A. Sivanandan When Memory Dies He sighed inwardly, this was not his day.
See also: not