YOU SAID:
Did I do something that you never done before?
INTO JAPANESE
私何かをする前にやったか。
BACK INTO ENGLISH
I did before you do anything.
INTO JAPANESE
私はあなたが何かをする前にやった。
BACK INTO ENGLISH
I did it before you did anything.
INTO JAPANESE
あなたが何かをする前に私はそれをしました。
BACK INTO ENGLISH
I did it before you did anything.
You've done this before, haven't you.