YOU SAID:

Aw, I can't believe you've done this.

INTO JAPANESE

ああ、あなたがこんなことをしたなんて信じられない。

BACK INTO ENGLISH

Oh, I can't believe you did this.

INTO JAPANESE

ああ、あなたがこんなことをしたなんて信じられない。

BACK INTO ENGLISH

Oh, I can't believe you did this.