"It just seems to happen when you are up against a former club. People seem to score. I don't have a celebration for when I score. Usually if I score, it's a surprise. I don't know when it is going to happen.
"It gave us a good start in the game and unfortunately we couldn't go on to get the second.
"But City are a top side who are going to challenge for the top four this season and, for us to play as well as we did, is a good sign for us."
The celebration of goals against former clubs has been a hot topic this season.
Manchester City striker Carlos Tevez refused to acknowledge his strike against West Ham last week while colleague Emmanuel Adebayor was fined £25,000 and given a suspended two-match ban for his celebration against Arsenal in September.
Dunne's actions were praised by both Villa boss Martin O'Neill and City manager Mark Hughes after the game.
"He was immense for us," said O'Neill. "He was determined to play well and his celebrations went down well because he did not celebrate at all.
"He is a great character and already he has given us all a lift here."
And Hughes added: "The City fans were fantastic in terms of the reception that they gave to Richard.
He is playing out of his skin at the moment
Manchester City manager Mark Hughes on Craig Bellamy
"He was a fantastic player over many years for City during the good and the bad times. Our supporters recognised that fact and it was really special."
The reaction given to Dunne was in stark contrast to that awarded to City midfielder Gareth Barry, who was back at Villa Park for the first time since his £12m transfer to Eastlands in June.
Barry was booed constantly throughout Monday's game, but Hughes dismissed it by saying: "The reaction was quite predictable.
"I'm sure people here appreciate what Gareth did for Villa but the minority made the louder noise. I don't think it affected him."
Barry ended the match with a stiff back but Hughes insists the 28-year-old is not a concern ahead of England's World Cup qualifiers against Ukraine on Saturday and Belarus on 14 October.
"I don't think he's a doubt for England," said Hughes. "We will send him along and get him checked by England but I don't think he's a doubt."
Hughes also paid tribute to striker Craig Bellamy, whose second-half goal - his fourth in seven league games - salvaged a point for City.
"He is playing out of his skin at the moment," said Hughes. "It doesn't matter what position I use him in, he is still having a positive impact on the game and it was the same tonight.
"He is playing with great confidence. He always thinks he is the best player and most of the time he has been."
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