it was one of those days

[Theseus]

Just one of those days . A day when everything goes wrong, as in:-
-- The car wouldn't start, I lost my glasses it was one of those days.
This expression was first recorded in 1936.

 

[drsiebenmal]

Hope you're not referring to today's elections, Th! ;)

OK, now that we have set this clear :), let's see some possible translations:

Είναι μέρα καταραμένη.
Είναι μέρα μουτζωμένη (my special favourite).
Είναι μέρα «ασταναπάνε» («άσε τα να πάνε»).
Μια μέρα που όλα πάνε στραβά.

 

[Themis†]

Ας προστεθεί και μια άλλη εκδοχή, λιγότερο εμφατική: Δεν ήταν η μέρα μου.