The Austria international, who is in talks to extend his contract at Villa Park, was recalled to the starting line-up for Friday night's FA Cup fourth round loss at Millwall.
That followed on from a humbling Capital One Cup semi-final defeat to npower League Two side Bradford and comes with Villa languishing in 17th place in the Barclays Premier League.
Darren Bent put the visitors ahead at the New Den but goals from Danny Shittu and John Marquis gave Millwall the win, with the Lions becoming the first name in the hat for the fifth round.
Weimann, 21, is calling for unity amongst the players as they look to get back to winning ways when they welcome Newcastle to Villa Park on Tuesday night.
"If you don't believe [you can turn it around] there is no point playing," he said.
"A month or so ago we beat Liverpool and Norwich and then it turned. We have got to stick together as a team now things are not going well."