YOU SAID:

I was tired, but she was down to party.

INTO JAPANESE

私は疲れていましたが、彼女はパーティーに行きました。

BACK INTO ENGLISH

I was tired, but she went to the party.

INTO JAPANESE

私は疲れていたが、彼女はパーティーに行った。

BACK INTO ENGLISH

I was tired, but she went to the party.