YOU SAID:
yesterday i am going to what are i doing?
INTO JAPANESE
昨日私は何をしているのですか?
BACK INTO ENGLISH
What am i doing yesterday?
INTO JAPANESE
昨日何してるの?
BACK INTO ENGLISH
What are you doing yesterday?
INTO JAPANESE
昨日は何してるの?
BACK INTO ENGLISH
What are you doing yesterday?
You've done this before, haven't you.