The Bantams face the Premier League outfit in the semi-final first leg at Valley Parade on Tuesday but looked off the pace against the Bees who scored either side of half time through Taiwo Atieno and John Oster.
Despite the setback, which saw Bradford fall out of the League Two play-off places, Parkinson believes the enormity of the Villa clash will be motivation enough for his troops.
"Win, lose or draw, on Tuesday it's the same game," said Parkinson. "We wanted to go into it with a win, but it wasn't meant to be.
"Going into the occasion on Tuesday we have to accept that Villa are three divisions above us and make sure expectations aren't too unrealistic.
"We're going to have to play very, very well over the two games, and they're going to have to perform below par.
"We want a performance that does the shirt justice, and that's what we intend to do. It's a massive event for the club. We will be swept away with it and rightly so.
"We've worked very hard to get to this stage and we're going to enjoy it.
"We totally dominated [Barnet] didn't we? We had 21 attempts on goal and to not score is very unusual, we conceded two goals at bad times which gave them a lift."
- Sports & Recreation
- Taiwo Atieno