After the opening-day victory at Arsenal, Paul Lambert's men have suffered three straight defeats but Weimann insists the signs are encouraging.
"After a defeat, you can't wait for the next game. That's the attitude in camp," he told the club's website.
"We all want to go again. We want to put things right and turn things around. We aren't down, no way."
Villa went down 2-1 at home to Newcastle last weekend, but Weimann says their second-half performance was encouraging.
"We aren't worried by the Newcastle defeat either," he added. "And, in fact, all the games we have lost have been tight matches.
"It's not like we've been blown away in any of them. They have been close, close games and another day we might have won all three of them.
"There's been one goal in all of them. Now we need to turn things our way.
"We were disappointed with the first half against Newcastle. We sat in too deep and couldn't get into the rhythm of what we're good at which is playing at a high tempo.
"We were much better in the second half. We really got into their faces. We got the goal back and thought we could push on for the win so to lose the next goal was very frustrating.
"We are best when we're playing quick football. That's what we have to do to succeed. We have loads of energy and great tempo. We showed that in the second half. We want to show that from the start at Norwich."