Playing at their first World Cup since 1974, Haiti were beaten by John McGinn's first-half goal but pushed the Scots hard late on, with Frantzdy Pierrot heading narrowly wide in the 85th minute and threatening again in stoppage time.
With Brazil and Morocco still to come in Group C, Haiti have their work cut out to advance but Migne said they are used to doing things the hard way.
"When you play a match, what you're trying to do is win," he told reporters. "On one hand, I'm very proud of what the boys showed tonight. It was a very good showing, with some good football.
"When we know where we're coming from, we rose to the challenge, but it makes it that much more frustrating that we came up slightly short."
Migne said his side must remain resilient and drew parallels with their qualifying campaign, when they had to wait until after their final game against Nicaragua before knowing they had reached the tournament.
"With Haiti, nothing is ever easy," he added. "If we are to qualify, it will be a struggle, and maybe it will happen in the last few minutes of the third game."
Haiti next face five-times world champions Brazil, before taking on Morocco in their final group match.
"We saw some fairly interesting things, but we're playing at an extremely high level, and just one oversight is enough," the 53-year-old coach added.
"You can get punished for that.
"We lacked that bit of spontaneity in our movement, in our combinations, and also had some poor decision-making at times," he said. "We'll have to score some goals if we want to have a chance to qualify."
The 2026 World Cup will be held from June 11th to July 19th in the United States, Canada and Mexico. The tournament will feature 48 national teams and will be played in 16 modern stadiums.
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