"They were ludicrous decisions," Bruce said.
"It is these kind of decisions which cost the likes of me my job because it affects the result of the match."
Bruce also felt that Blues should have capitalised upon Stern John's second minute goal.
He said: "It was a great start but then we went flat. It shows John is a potential match winner."
"Failing to beat Portsmouth means that we now have another big match against Crewe on Wednesday when it will be vital for our supporters to get behind the team yet again."