Rooney was banned after being sent off for kicking Montenegro's Miodrag Dzudovic during England's final Euro 2012 qualifier in October.
Asked if he needed to channel his aggression in the right way on Tuesday, he said: "I think I have done all season.
"What happened [in Montenegro] was a mistake. I understood that and apologised to the guy.
"I've paid the price. I've had to take it.
"And I have no problems with my attitude or my temperament. I'm happy and I'm ready to play."
Rooney admitted he feared his suspension - which was originally three matches before a Football Association appeal reduced it to two - would cost him his place in England's Euro 2012 squad.
"Of course," he said. "Certainly, when it was a three-game ban, I thought I probably wouldn't be here."