Dunne said: "You can't legislate for errors in the passing, but I'm not going to lambast people here.
"The headlines are we have gone 10 games without a win, but that masks the way my players have been playing.
"We've been punished three times for giving away possession. It's as simple as that.
"But we have a strong enough squad to bounce back. The stats show we have lost many points when we've been in the lead, but that will change."
Dunne added: "The Brentford fans came here with a different agenda.
"The atmosphere was flat and we wanted to capitalise on that, but you can't make mistakes like that against a side like Brentford."
Ukuonghae gave the visitors the lead just after the break, rising unmarked to power home Luke Garbutt's corner.
But the Bees hit back in the 76th minute when Trotta slotted home Clayton Donaldson's low near-post cross.
Chelsea loanee George Saville put the home side ahead with 10 minutes remaining, firing home a curling drive from the edge of the area.
And the comeback was complete with minutes to go when on-loan Cardiff winger Kadeem Harris headed his debut league goal from Sam Saunders' precision cross.
Brentford might have gone in ahead at the break, but Trotta fired wide from three yards when it looked easier to score.
- Sports & Recreation
- Marcello Trotta
- Kadeem Harris