Former skipper Henry was given a straight red card 15 minutes from time with the score 2-2 after kicking out at Villa winger Marc Albrighton. He acknowledges his error "cost" Wolves the game as a late Robbie Keane goal earned Villa a 3-2 success at Molineux.
Henry, who now faces a three-game ban, said: "It was frustrating as I was trying to get to the ball and Albrighton was holding on to my leg. I was trying to get to the ball and I just kicked out in frustration to try and get away. As soon as I did it, I thought 'what have I done' because you can't react like that on a football pitch."
He added: "Albrighton made the most of it but I know I shouldn't have done it. I hold my hands up, it was a bad error of judgement and a terrible reaction which you just can't do.
"Ultimately it has cost us. We weren't in front at the time but were level and I left us with 10 men for the final 15 minutes which saw them go on and get the winning goal. I have cost us."
Henry added: "I have apologised to the manager and the rest of the lads and would like to apologise to the fans as well because it was really poor.
"It's going to be a long month now for me without being able to play for three games.
"I've got to sit it out for three vital games but I'm sure the boys will do the job and get us out of the relegation zone. On the plus side we've been playing well over the last six weeks or so.
"The performances have been much better and we may have drawn a fair few games but only lost one over the Christmas period and that was a late goal to Chelsea.
"It was another good performance on Saturday and I'm really disappointed we didn't get anything."