YOU SAID:

My back has been hurting horribly for over a month.

INTO JAPANESE

背中が1ヶ月以上ひどく痛いです。

BACK INTO ENGLISH

My back has been hurting terribly for over a month now.

INTO JAPANESE

もう1ヶ月以上、背中がひどく痛いです。

BACK INTO ENGLISH

I've had severe back pain for over a month now.

INTO JAPANESE

もう1か月以上ひどい腰痛に悩まされています。

BACK INTO ENGLISH

I have been suffering from severe back pain for over a month now.

INTO JAPANESE

私はもう1か月以上ひどい腰痛に悩まされています。

BACK INTO ENGLISH

I have been suffering from severe back pain for over a month now.