YOU SAID:

I feel incredibly old although bring young.

INTO JAPANESE

私は若くしても信じられないほど年をとっています。

BACK INTO ENGLISH

I am incredibly old even if I am young.

INTO JAPANESE

私は若くても信じられないほど年上です。

BACK INTO ENGLISH

I am incredibly young even if I am young.

INTO JAPANESE

私は若くても信じられないほど若いです。

BACK INTO ENGLISH

I am incredibly young even if I am young.