Head coach Johannes Hoff Thorup was left frustrated by missed opportunities and a poor first half after his side fell 1-0 away to Swansea City in the Sky Bet Championship.
An own goal from Amankwah Forson in the fourth minute would ultimately settle the tie.
"You can only get something out of a game if you perform on a level we can expect and we didn't do that today," Hoff Thorup said.
"I think the first half was not good enough in terms of what we expect from the group and we allowed them to score a goal more or less out of nothing in the beginning of the game and then of course it's a little bit tricky.
"I liked the response though; I like that we created two big chances more or less straight after, but overall we have high expectations for how we want to perform.
"We have to look more into our own game where the first half is maybe too even. The second half was ok, we have the control that we want and we created the chances that we needed to get some points from here but we were not good enough in the first 45 and that we have to look into.
"We're still building here, we have to create a base, we have to create a foundation within the team where we can more or less go from game to game and perform on the same level, but we are not there yet and I think today was for us to see that we still have some steps."
The head coach was hopeful that Anis Ben Slimane's absence will be short-term:
"He felt something on Friday and we decided not to take any risks with him. Hopefully something minor, hopefully something he can recover from quite quickly. We can hope to have him back on the pitch next week."
Looking ahead to the game with Watford at Carrow Road:
"Every game we play is important and we have to make sure we do enough to win them and now we have to analyse this one and make sure we can perform better, especially the first half of the game when we play against Watford on Saturday."