"I picked up my first booking in my first tackle of the game when you would normally expect a warning to be given," said Mackin.
"As for the second yellow I felt the ball was there to be won and I thought that's what I did. Looking back now I know I should have stayed on my feet.
"We had been told beforehand that officials would stick to the letter of the law, but to be honest I thought he ruined the game because he was blowing up for virtually every minor physical contact.
"If we had been five or six games into the season I think I might not have been sent off."
Mackin's exit from the field came within nine minutes of the red card shown to Stevenage striker Steve Morison and the Dragons player went on: "The referee could not wait to show me a second yellow and it was as if he wanted to even things up.
"But it's a hard lesson for me because I'm suspended for the next game. I worked so hard during pre-season to be in the starting line-up and now I've lost my place and it might be difficult to win it back straight away.
"I'll be very, very disappointed if I'm out of the team for a while and it's something I've been thinking and worrying about ever since it happened. But it's an incident I will certainly learn from and next time I'll consider the possible consequences before diving in."