Assessing the game in Wales having looked at the video to confirm what he saw at Ninian Park, he admits:
"It was a massive disappointment just in the manner we lost the goals; okay, we have not been scoring as a team, but we have looked solid enough defensively.
"But the other evening they were very poor goals - what you would expect in the playground, to be honest.
"We probably created as many chances in the game as we have in any other games away, and played nowhere near as well as we can do.
"It was a very strange and disappointing performance to say the least, especially with the goals we lost - you are always on the back foot when you concede two goals like we did so early in the game.
"The team have not been scoring enough goals so the back four have been very vigilant in what they have to do and have been keeping things tight in most games.
"The manner in which we lost the goals was comical in some circumstances - but the players know they let themselves down badly.
"We didn't retain the ball as well as we should, all the hallmarks of a good side away from home.
"We knew they were playing very well in recent weeks so that meant we had to do our job properly - but to defend how we did, at a difficult place at the best of times, made it so hard.
"In that game we had three shots cleared off the line so it could have been different, but losing the last goal was farcical - though, having said that, you have to throw caution to the wind to try and get something from the game.
"But to say it was a long journey back is an understatement after that sort of performance."
He is not attributing blame to any one area of the side and explains:
"We always say you win as a team and you lose as a team; you score goals as a team and you defend as a team - and when people say we don't score enough goals they automatically think of the strikers.
"But if strikers are creating for others that is worth its weight in gold as well, just as your first line of defence is your forwards.
"We let ourselves down badly on Tuesday and that is the disappointing thing because we have done that too many times with the quality we have at our disposal - it has happened too often, that's for sure.
"We keep talking about the consistency of performance; there are too many performances where we say we want to put that to bed, thankfully the games are coming thick and fast, we'll bounce back and show strength of character - but the performances have to be far more consistent and better, and there is no use hiding from it and saying that the players have responded in training.
"That becomes rhetoric - we have always trained well but on a Saturday and a Tuesday there have been too many occasions where we have let ourselves down badly considering the quality we have.
"Yes, you expect them to be disappointed because, just as it is for the supporters, it is hard to take in your stomach - we feel the exact same way.
"There is not a better than feeling getting up in the morning having played well and won a game of football but the feeling is the complete opposite when you lose and I have felt that way too often."
Peter is satisfied with the home form, though, and adds:
"The home form has been fine, but I go into every game expecting to win the game whether home or away; I wouldn't be saying that if I was with a team that wasn't good enough but I can honestly say with my hand on my heart with this group of players I go to games feeling confident; unfortunately, though, there have been too many Jekyll and Hyde performances.
"We seem to be saying the same thing and it gets to the stage where we have to put it right on the training ground - and on the pitch where results obviously count.
"We need to maintain the home results but still look for even better performances; there has been nothing that has been fantastic in any shape or form.
"We have to put one in that sets things alight; it is time for action now, rather than talking about it."
He says that looking at the other contenders is largely wasted energy and adds:
"I don't worry myself about Wigan or anyone else; we have to get our own house in order and I have always said from day one we can win the Championship if we do our job correctly.
"Sunderland and QPR have had great runs but there is nobody that I set my sights on; if we do our job we will be in there.
"We are letting ourselves down, it is not the Wigans of the world letting us down, because they are paid to win as we are - but we are not doing it on a consistent basis."
As for Teddy Sheringham's injury, Peter adds:
"It is one of these injuries that you can't take a chance on or it would become a major problem; there are certain injuries you can play through but not this one.
"We have missed him, there is no doubt about that, but we still feel we have enough players that are capable.
"People raised a few eyebrows in the summer when we signed him but we knew the quality we were getting and he has proved that.
"He is an integral part of the set-up but we can't afford to lose him for too long by taking a chance on him."