Villa won 1-0 at Old Trafford, following a goal by Gabriel Agbonlahor.
“This win will give us a great deal of confidence but that could quickly be eroded at Sunderland on Tuesday,” said O’Neill
“It is a really great win, and I am not trying to play it down, but the main thing is the players should be really delighted with their performances against sides that they normally find it hard against.”
