Sylvan Ebanks-Blake's fourth-minute goal was enough for Wolves to take all three points at Hillsborough on Saturday and stay out in front in the Championship.
After recording only their second win since December 20 by beating Crystal Palace in midweek, Wolves now look to be back in form as they approach the final hurdles in the promotion race.
"I hope that's the case," McCarthy said. "The performance would suggest that and of course the result would as well. We've played well in the last couple of games."
With the match barely under way, Ebanks-Blake got in front of Richard Hinds to head home Michael Kightly's cross at the far post.
The match was more comfortable than the final result suggested as Wolves could have added a couple more in the first half before digging in after the break to make sure there was no way back for Wednesday.
"I thought we were excellent in the first half," said McCarthy. "They broke on us once from a free-kick and Jermaine Johnson had a glorious chance and blazed over but other than that I don't think anything caused us any problems."
Indeed, it was Wolves who went closest to a second with Kightly denied at close range by Lee Grant before George Friend headed just wide.
The second half was a different story as chances became few and far between for both sides, Johnson again wasting the best of them as he met Marcus Tudgay's cross with a weak shot in the 77th minute.
"In the second half, I expected Sheffield Wednesday to make more of a fist of it and they did but I don't think (goalkeeper) Wayne Hennessey was diving around making too many saves," McCarthy said.
With Birmingham beating Southampton, Wolves needed this win to remain three points clear at the top in the Championship.
"We're top of the league, everyone's chasing us and snapping at our heels so what words can you find to stress how important it is to win games?" McCarthy said. "It's vitally important."
For Wednesday, this is a second narrow home defeat to a promotion contender in quick succession following the 2-1 loss to Reading on Tuesday night.
"I would say it tells us how far away we are rather than how close," Brian Laws said of the results.
"I look at it this way - both teams have got themselves in a position now where they've got to be solid. They're not really interested in how they play, it's more about results and today really typified that from Wolves."
Laws revealed he had chosen to rest Mark Beevers and replace him with Hinds, but was left to question that decision after seeing the ease with which Wolves scored.
"The goal was really, really disappointing because it was basic schoolboy stuff," he said. "We've allowed them to put in a simple cross from a throw-in and then we have a static defender.
"They got the goal they needed and then the game became a battle because they were fighting to keep hold of it and didn't let us play football.
"Well done to them. They know how to win a game 1-0 and we don't."