Wales manager Rhian Wilkinson says the achievement will “change everything” for Welsh football.
“This team found a way. They never broke up, they stayed strong. I’ve never been more proud of a team,” she said.
“This is a special team. My staff is of another level and this team, because it doesn’t give up… it never does things the easy way.
“This team relies on giants who came before and have now shown how good they are.
“They are better than they think and they just have to see it, live it and experience it.
“Those boys and girls at home are watching a generation of football that will change everything.”
Wales goalscorer Cain, who has recovered from two knee surgeries following ACL tears, admits she struggled to contain her emotions.
“Honestly, I have no words. There is nothing that can compare to this feeling,” he said.
“You can see what it means to everyone. I was crying when I scored.
“It’s very emotional. I’m glad to be doing that again. I’m not going to lie, I was a nervous wreck. But this is what dreams are made of.”
Former Welsh defender Danny Gabbidon believes qualifying for a first major tournament could be a seismic moment for sport in Wales.
Gabbidon says the impact of the victory could be similar to that of 2016, when the Wales men reached the European Championship, their first major final in 58 years.
“It’s incredible. It takes me back to 2016, when the boys did it,” he added.
“It’s the same kind of feeling.
“We’ve had so many disappointments to be in that draw, for little Wales… we’re going to show Wales.”
