Krul, along with the likes of Fabricio Coloccini and Steven Taylor, has already missed big parts of the season but now all three are back to full fitness.
"We are getting our solid unit back again," he told the Sun on Sunday.
"We had a few injuries at the start of the season and haven't been playing with a solid back four as we did a year ago. We had a real solid base last season, but even I have been injured and out for a few weeks, so it's nice to get everyone back fit again.
"My injury couldn't have come at a worse time. I was given the Holland goalkeeper's shirt, played the game and got injured.
"I was sad because I love playing for Newcastle."
Last season's goalscoring hero Papiss Cisse has also failed to recapture his brilliant form of the last campaign after joining in January and he is yet to score this term.
But with Demba Ba showing good form, Krul is confident they will soon both be finding the back of the net.
"The same happened last season. If one wasn't scoring then the other would step in," he said.
"The season so far, it's not been the best. We were spoiled last year because we had an unbeaten start of 11 games. Of course people will try to compare this season with the last, but over the next five games we will be playing the teams around us and they are the ones we need to take points from.
"We have Liverpool coming up, as well as West Ham and Swansea. These are the matches we need to win, especially at home."