Marcus Tavernier had Bournemouth ahead midway through the first-half via a penalty before Charalampos Kostoulas struck a superb overhead goal a minute into injury time for Brighton's equaliser.
Iraola said afterwards: "It is very harsh, very harsh for us because we were so close to getting the three points. We played a really good first half and had our chances, we scored one and we were controlling the game.
"In the second half we didn't have the energy to keep these intensity levels and we had to defend a little bit lower, especially after the Brighton subs, but we were doing well. At the end it is an incredible goal from Kostoulas.
"We had to defend deep and compact, and as we did in the first half you have to come together a bit more. You know you are probably going to concede some set pieces and you have to do the basics and defend your box.
"I have seen the (Brighton) goal, and it is very difficult to blame the players. We had Senesi in front of him but it is a bicycle kick, outside top corner, it's incredible. Looking at the replay I was trying to see what we could do better but it is impossible.
"Lately we have been very close to winning, and in difficult stadiums, for example against Newcastle in the cup, lose on penalties. Maybe before the game you say one point is good, Brighton away is a difficult place, but seeing how the game has evolved we might not think it is good for us."