"We are pleased with the performance but the nature of this football club is we will look at what we need to improve upon, and there were elements of our game that can get better," said Lee.
"We could have scored more than five but for Shay Given who was very good for Newcastle but to win 5-1 we must be pleased with that.
"All we can do is focus on doing our job. St James' Park is never an easy place to come and get three points but we have done that.
"Full credit to our boys with the way they always work hard and they are willing to improve every aspect of their game.
"We've had our critics this season but we know our job and what we want to do.
"We know there is improvement to be made and we will be working very hard to ensure we do improve in certain elements of our game."