Milner spent four years on Tyneside and admits City still have it all to do to claim their first title since 1968.
The midfielder said: "The game against United was massive and a big result for us - but we can't get carried away.
"We've got two games left and it will be just as difficult, maybe even harder, going away to St James' at the weekend.
"That's obviously the next thing on our minds. If we can get a good result there then it's in our hands."