The manner of the loss was particularly hard to take, as the Cottagers fought back strongly and looked on course to earn at least a point at St James’ Park.
However, a last-minute strike from Bruno Guimarães denied them a share of the spoils.
“Of course, we’re very disappointed,” Iwobi told the website. “We knew it was going to be a hard game and a tough place to come to, but if we don’t win then we shouldn’t lose, and maintain the draw.
“Unfortunately, a last minute winner is a dagger in the heart, but we have to pick ourselves up and go into next week’s game.
“Going into the second half, we had the bigger spark. Obviously, there was a lot of changes, there was a lot more dynamism going on down the flanks, so we were able to hurt them and create a few chances, but if we don’t take our chances, good teams like Newcastle can punish us.
“We were able to create chances against a great Newcastle side. We limited their chances as well, even though a couple of mistakes punished us.
“As long as we stay consistent, give 100 per cent and stay focused until 90-plus minutes, I’m sure we can get the results that we need to.”