The Villans won the second leg of their tie 2-1 at Villa Park, but crashed out of the competition 4-3 on aggregate following their defeat in the first leg away from home.
"I am absolutely gutted, hurt, disappointed, everything," he told BBC Sport. "You can either lie down or come out fighting and I will come out fighting."
"We will never have a better chance to get to a cup final throughout our whole careers.
"I can't repeat what was said to the players in the dressing room and no manager would tell you that, but everyone is hurting. They might take 10 or 12 years to even get close again."
Villa are currently just a point and a place above the relegation zone in the Premier League table.