YOU SAID:
what the heck are you doing?
INTO JAPANESE
何してるの?
BACK INTO ENGLISH
What are you doing?
INTO JAPANESE
なにをしているの?
BACK INTO ENGLISH
What are you doing, man?
INTO JAPANESE
なにをしているの?
BACK INTO ENGLISH
What are you doing, man?
That didn't even make that much sense in English.