Donnacha O'Callaghan admitted Ireland felt "a bit ashamed" by Sunday's 12-8 RBS 6 Nations defeat to Scotland at Murrayfield.
Four penalties from Greig Laidlaw sent the Irish crashing to their second defeat of the championship, destroying any faint hope they had of challenging for the title.
O'Callaghan insisted the players should only look at themselves for an explanation of their latest implosion, and said: "This will dent our confidence and we must be honest with each other. It wasn't good enough by us today. We're not at Test level to learn, but to win."
He went on: "You can look around at other people, but it's man-in-the-mirror time. No fingers are being pointed. That first win in Cardiff does feel like a long time ago.
"Playing for your country is special but you need to get results. You need that buzz, but this feeling is horrible.
"You feel like you've let everyone down and that's the worst part. You're a bit ashamed and that's the way the players were in the dressing room.
"No one was eyeballing each other, everyone's just scurrying around the place. It's a horrible way to spend the next few weeks."
Ireland dominated territory and possession by 71% and 77%, while Scotland's tackle count was 128 to their 44, yet they still left Edinburgh with a chastening defeat.
Next up are winless France, their nemesis over the past decade, in what has become a must-win encounter.
"It's a hard defeat to take, a hugely disappointing one. We're gutted and feel a bit empty," O'Callaghan said. "When you have that much territory and possession, you have to come away with more. But we were confident at half-time that we'd knocked some of the wind out of them. When winning moments are there you have to be good enough to take them, but we came up short in that."