The Lambs are without a boss after parting company with Andy Morrell last week.
They went down 2-1 at Alfreton on Saturday but it got a lot worse on Tuesday night - the side’s National League North campaign took a turn for the worst with a 3-0 home defeat to Blyth Spartans.
Stand-in Fowler wants his players to accept they are in trouble and he told the National League’s Oli Osborn things must change.
“Standards weren’t good enough and that’s not something I can just accept,” he said.
“Our position in the league dictates that we can’t accept that - as a group we have got to be a lot better.
“The first half performance was possibly the worst I have seen in recent times.
“We were a couple of yards short in every area. We knew what kind of a threat Blyth would pose and we didn’t deal with it.”
Tamworth are now just five points above the bottom three.
“Playing Saturday isn’t an excuse,” Fowler added. “They did too and we were very poor all over.
“The fans here expect more. They want to be winning games and at the moment we’re not.
“When you are in a dogfight - and at the moment we are in a dogfight - then you need to actually fight.”