YOU SAID:
she was tired because she didn't really sleep at all
INTO JAPANESE
彼女はまったく眠れなかったので疲れていた
BACK INTO ENGLISH
she was tired because she couldn't sleep at all
INTO JAPANESE
彼女はまったく眠れなかったので疲れていた
BACK INTO ENGLISH
she was tired because she couldn't sleep at all
Well done, yes, well done!