He said: "I've felt its been over for a number of weeks if I'm honest, we've lost crucial players and we aren't good enough.
"We had our chances and you can see we've got decent players but we just haven't got a squad to cope with a number of injuries."
He added: "I'm disappointed we're not in the play-offs, 2-0 up at Burnley last week, 1-0 up today but it's because we're not good enough and I don't like to be not good enough.
"I don't mind if I'm good enough and we get beat when we shouldn't get beaten and it's disappointing. But the fans understand the financial situation at the club, it's crucial we get five or six Bosmans, I don't think we'll be able to pay any money out."
The former Sheffield United boss slammed his side's defending and admitted the Tykes were worthy winners.
He said: "We couldn't cope with the quickness of their breaks and we were our own worst enemies. We created most of their breaks. That is really Sunday league defending.
"Credit to Barnsley, I thought they deserved it, they pushed their luck a little bit and the crowd got behind them and they deserved it."
Simon Davey was delighted with his sides bounceback after no win in their previous three games.
Davey said: "We asked for a reaction from Saturday and we got everything we asked for.
"We went behind after a mistake from Stephen Foster, but the way we bounced back and the character we showed was fantastic. We were a lot more dangerous than them and we were the better side and deserved to win."
The South Yorkshire club still have two games in hand on fellow strugglers Nottingham Forest, Norwich and Plymouth and Welshman Davey is confident they will avoid the drop.
He added: "We are now looking up, there was doom and gloom at the weekend when we went into the bottom three but we're looking up now and will try and catch Derby, who are three points ahead of us.
"I think we know what we need to do to stay in this division, we have to stay focused as a team and management. We're not out of danger, but we know what we have to do."