Shaun Wright-Phillips had earned the spot kick and settled the outcome with a second goal late on.
"We should maybe have been out of sight after the first half.
"But in the second half we showed another side to us and we were resolute and hard to beat.
"It was probably the best we have played."
Villa are now only three points clear of fifth-placed Arsenal - their rivals for the last Champions League spot.
"We didn't play well enough in the first half. We just did not get to grips with the game early on.
"We came out with determination and we had plenty of the ball in the second half. We were camped around their area but we couldn't break through.
"It is disappointing but we are still in the fight. It has been a bad few days - but that cannot be helped now."