Iraola’s side dominated the game against Arsenal but were unable to convert any of their chances as the reigning champions reclaim top spot.
Kai Havertz scored the only goal, sneaking in at the far post to slot beyond Alisson in the Liverpool goal, to secure Arsenal’s first Premier League win at Anfield in 14 years.
Liverpool were denied a penalty from Jurrien Timber’s pull-on Alexander Isak, preventing the striker from reaching the ball and head towards goal.
Speaking to BBC Radio 5 Live after the game, Iraola insisted his side deserved more.
"Disappointing for us. We definitely deserved to score but weren't able. We regret the first 15 minutes until we conceded the goal but I loved after," he said.
"We changed a little bit by being more brave and aggressive and we put them under pressure. We had some chances that we haven't finished properly. Also they have been good defensively."
On refereeing decisions: "I think the Alexander Isak penalty was very clear. Everyone sees how they grab the shirt. I don't understand. I think it's because he doesn't dive. The shame is that we have to tell our players to dive. It is so clear and it is a great chance for us."
On a potential Arsenal red card: "I've just seen one replay. I think a red card has to be more clear movement. It didn't look like a clear red card, no.
"There are a lot of positives but it's not enough against these teams. We had very good situations inside the box that we haven't finished properly but I value how we played after the 1-0 a lot."
On the momentum going in the right direction: "It's difficult to say after a loss, coming from five wins. This game was important for us and it feels disappointing."