He was responsible for one of Lancaster's three goals on Bank Holiday Monday and was criticised by boss Jim Vince after the defeat at Mossley.
But he has bounced back in style over the past 10 days and is determined to continue to improve.
"I had a couple of nights thinking I had to buck up," he admitted.
"I didn't clear the ball at Lancaster away, they scored from it and I was dragged off at half time.
"But it happens and I went home, thought about it and it makes you stronger.
"If you make mistakes you have to learn from them."
He could hardly have made a bigger impact than he did seven days ago against Salford City at the Shay when he bagged the opening goal after just 46 seconds.
Remarkably he was furthest man forward in an early Halifax attack, something he was allowed to be because of the new 3-5-2 formation put in place by the manager.
"The manager has given me that role," said King. "We have enough players at the back so when Cavell has the ball on the right, it is my job to get round the back.
"The shot from Ashley was going in, but I got my shin on it and the keeper saved it.
"I smacked it in and it was a cracking feeling in front of the Town fans."
Within 90 seconds of King scoring, Paul Gedman added a second against basement club Salford.
With the game effectively over as a contest, Town went on to lead 5-0 at the break before cruising to a 7-1 victory.
"It was a weird game because they kept the ball quite well at the back," said King. "But we got two quick goals and a third after 15 minutes or so.
"The manager still brought up negatives. He wants perfection - and rightly so.
"But it is hard when you are 5-0 up to go out and do it again."
King will now be hoping to maintain his good form and that the boss sticks with the new formation.
"The system suits both me and Cavell Coo," he said, "The first couple of weeks it was a matter of keeping our shape.
"But we have three centre backs who are all capable with midfielders in front of them.
"It gives us both the licence to go and join in and I love it."