The 27-year-old was deservedly sent-off for a wild lunge on Jordi Gomez just 11 minutes into their Premier League contest at the DW Stadium.
Referee Lee Mason had no qualms issuing a straight red card and despite Henry's protests he now concurs with the official's initial decision.
Henry regrets the needless challenge and believes that if he had a chance to recreate the incident that he would have stayed on his feet.
The former Stoke man is backing himself to learn from his rash decision and is gutted he will now be missing games through suspension.
The contest was goalless when Henry was sent off and he firmly believes the club would have gone on to win had he not lost his head rather than the 2-0 they eventually suffered.
"Having watched it again I can see that it looks horrific and realise that it was a deserved red card," he told the club's official website.
"I've already apologised to the manager, TC and the boys, but I'd also like to apologise to the supporters, especially the ones that travelled up to Wigan.
"If we had had 11 men on the pitch, there is no doubt in my mind that we would have won that game.
"I'm desperately disappointed - if I could go back and rerun it all again I wouldn't make the challenge and I would have stayed on my feet.
"It's something that I'll learn from. But things happen so quickly. I'd made the decision to go and win the ball and it turned out to be the wrong one.
"We started really well and I thought we were well in contention - especially in the first half. And so again, I'd like to stress how sorry I am because I know that I have let people down.
"And, on top of everything else, I'm going to miss three important games. For me it's a bad situation, but I've got every confidence that the boys can get a result against West Ham and kick on from there."