YOU SAID:
I have not eaten in a few days
INTO JAPANESE
私は数日食べていません
BACK INTO ENGLISH
I haven't eaten for a few days
INTO JAPANESE
何日も食べてない
BACK INTO ENGLISH
I haven't eaten for days.
INTO JAPANESE
何日も食べてない
BACK INTO ENGLISH
I haven't eaten for days.
That didn't even make that much sense in English.