Liam Delap had Ipswich ahead at halftime before Wolves stormed back to win 2-1 via goals from Pablo Sarabia and Jorge Strand Larsen.
McKenna said: “I think it was a really competitive first half, the players gave absolutely everything to the game, to the first half and to the second half.
“At 1-0 up, Wolves are a good team, so if you don’t manage to go and get a second goal then they’re going to put some pressure on.
“They put some pressure on, we probably weren’t able to maintain our energy levels that we had in the first half, which was fairly to be expected after the effort that the players put into the game on Wednesday night and some of the physical challenges that we have in the squad at the moment.
“So we weren’t quite able to maintain our energy levels. Wolves had a strong period probably from half-time to about 60 minutes but I thought we had seen that off and steadied a little bit and we had some set plays and some little opportunities, probably between 60 and 70 minutes, but we weren’t able to go and get the second goal.
“And then the goal goes their way and that changes the game. You can say it’s maybe a slightly fortuitous goal. We were all back, we were defending, we blocked the first shot and it popped up to Sarabia’s foot and he bobbles it into the corner.
“You can say it’s another goal from a Spanish international, who’s come from PSG, who has come off the bench fresh and managed to find the big moment to pull Wolves back into the game.
“At that point, it felt like they had all the energy and confidence on the pitch and we weren’t able to quite find the response and we weren’t able to do enough to get the result.”
McKenna added: “The likelihood is that we’re going to fall short of our ultimate dream at the end of the season.
“There will be plenty of time to talk about that and analyse that and reflect on the positives and the negatives throughout the course of the season, but for now I don’t see too much changing in the next seven games.