Wayne Rooney netted the only goal of the game at St. James' Park as the Magpies succumbed to their eighth successive defeat in the Premier League.
The midweek result leaves Rafael Benitez's outfit 16th on the table, two places above the relegation zone.
“I believe we created a lot of chances, we could have scored more goals and won the game, but that’s football,” Atsu told his club's official website.
“We conceded, they all went back and we tried to break through them. In the second half, I think they were more defensive, but in all we were the better team and unlucky that we lost.
“From what I have seen, I think we are improving – especially in this game, and even in the Leicester game, we have improved.
"They didn’t create more chances than us – like I said, we were unlucky. I think defensively we were better and offensively we were good, so that is a positive thing for the team."
Next up for Newcastle are Arsenal.
On Saturday, the Magpies will be chasing a return to winning ways against a side who have also set sights on three points following consecutive draws.
“We will keep fighting and working hard," Atsu vowed.
"The next game is the most important.
“We know Arsenal will be very difficult – the same as this one. Every game is very difficult for us, but we need to keep working hard and try to keep a clean sheet."
So far this season, Atsu has made 13 league appearances involving 11 starts and a goal for Newcastle.