YOU SAID:

I am not having a good day.

INTO JAPANESE

私は良い一日を過ごしていません。

BACK INTO ENGLISH

I haven't had a good day.

INTO JAPANESE

良い一日はありませんでした。

BACK INTO ENGLISH

I didn't have a good day.

INTO JAPANESE

良い一日はありませんでした。

BACK INTO ENGLISH

I didn't have a good day.