Su McCaughan watched online at home in Wilmslow, Cheshire as her 17-year-son played over a hour in the 2-0 defeat by Turkey in New Britain, Connecticut.
Husband Mike Gorman was unable to share the moment as he was attending a business conference in Antwerp.
Now Johnny is expected to get another run-out in the final match of the mini-tour in Chile on Sunday against the World Cup finalists.
Su said: "We are immensely proud of Johnny and cannot quite believe it is happening.
"My husband would have gone to Connecticut to see the match but had other commitments.
"We managed to watch it online. As a mother I was only watching Johnny play, not really the game. He put in a couple of good tackles and got a yellow card. I think that will go down well with him!
"He did not seem to be fazed by the occasion. When he came out at the beginning he looked quite comfortable."
Gorman moved to Wolves in the summer after spending six years with Manchester United. A former pupil pupil at Wilmslow High School, he now attends Repton School after winning a scholarship.
He qualifies for Northern Ireland through his mum, who was born and brought up in Coleraine and retained her maiden name after marrying.
She said: "Johnny has played for Northern Ireland at youth level but to be called up for the senior team was a real big jump. Being with the older players will be a good experience for him.
"The Wolves Academy have been really supportive of Johnny. The partnership between the family, the school and the club is a unique model. No-one has ever done that before and it is working.
"Repton was a marvellous opportunity for him but the first few months were difficult for him.
"It is quite a step up from GCSEs to A levels and he was balancing part of the week at Wolves and part of the week at school. It was the first time he had been anyway from home for any length of time."