YOU SAID:

I farted so hard that I have fallen down and I cant get up.

INTO JAPANESE

倒れて起き上がれないほど激しくおならしました。

BACK INTO ENGLISH

I fell so hard that I couldn't get up.

INTO JAPANESE

私はとても激しく倒れたので起き上がれなかった。

BACK INTO ENGLISH

I fell so hard that I couldn't get up.