Blues dominated Posh for the first forty-five minutes of the game at St Andrews on Saturday afternoon but only led by a solitary Marlon King goal at the interval.
They were made to pay for their inability to see off their visitors when Grant McCann equalised for Posh early in the second half.
"I am immensely frustrated and disappointed to be part of a game where we dominated the first half and didn't win," the Blues boss said after the 1-1 draw.
"I think the problem when you have such dominance is that you have to put your chances away.
"At 1-0 at half-time I still felt we would go on to win the game. In free play I could not see them scoring a goal. But we gave away a poor free-kick on the edge of the penalty area and Grant McCann has that type of quality to score.
"You have to give them credit for getting back into the game and McCann for making that type of delivery at an important stage of the game.
"To maintain the tempo we showed in the first half for 90 minutes is very difficult but we have to be solid and it is a game in which if you are able to maintain this tempo you win the match 1-0."