North End were wasteful in attacking areas at Deepdale and could have easily won the game, though they could not carve out the openings they required.
Patrick Bauer had given the Lilywhites the lead after getting something on Alan Browne’s volley from the edge of the box 31 minutes into the game.
Four minutes from the end, however, Scott Hogan’s header gave Birmingham a point, after they had started to put some pressure on the home side.
There were several occasions where a different decision may have led to a different result as PNE got into good areas and Whiteman felt they let recent standards drop.
He said: “They’ve got every right to be disappointed, we’re disappointed in the dressing room. It’s a poor one to concede from our point of view.
“You can flip it and say we weren’t great going forward today.
“That’s the most disappointing thing, we’ve set the standard under the new manager of finishing those sorts of moves off. That’s the most disappointing thing from us today, our final pass.
“It’s positive that we’re getting into those areas but the main thing is that now you have to finish them off.
“When you expose teams and get into good areas it’s about taking chances and putting the ball in the right areas.
“We said at half time if we could get the second goal we could go on to get a few more.”
After leading for over half of the game, North End’s No.4 had to settle for just a point from the game, despite him feeling they deserved more.
It is still seven points from nine in the Championship under new boss Ryan Lowe. however.
Whiteman said: “From our point of view you want to see the game out but get the next goal, it’s a fine balance.
“It’s a difficult one to take on the balance of the game, we got into the final third and the final pass let us down a little bit.
“To concede in the last minutes is always gutting but I think you have to take the positives.”