Hughton's men have struggled for consistency since their 10-match unbeaten run ended, winning only twice in 2013.
"We are massively disappointed and frustrated," said the Norwich manager. "It was a game I don't think we deserved to lose.
"We were very good in the first half, but we knew what Villa's strengths were, and the quality they have. We kept them quiet for most of the game, but conceded two poor goals.
"We were a threat in the final third, but you have got to score goals, which has been difficult for us."
Despite Norwich's poor run of form, Hughton remains optimistic.
"We are in a battle, we know that, but it is still in our hands," he said.
"We have two games left, the next is at home to West Brom, so we need to make sure we dust the players down and make sure we show a lot of the good things which we did do, because we will need every bit of that next week."