The match at Nizhny Novgorod Stadium saw Sweden missing a clear chance in the 20th minute as they controlled the pace throughout the first half.
The Swedes were awarded the penalty after referee Joel Aguilar consulted a video screen on the sideline following an appeal by the Swedish players.
But from his vantage point, Shin thought otherwise. "I think he probably tore it", Shin said after the game.
"I don't think that it's only our height that matters".
South Korea are ranked No.57 in the latest Federation Internationale de Football Association rankings while Sweden sit at No.24.
In truth, there was more intrigue and excitement in the build up to the match, with Sweden manager Janne Andersson apologizing after a member of the Sweden coaching staff was caught watching a South Korea training session. Shin made a surprise starter out of forward Kim Shin-wook, the tallest South Korean player at 197 centimeters. However, the absence of Zlatan Ibrahimovic was certainly missed as too many chances were missed.
Berg was denied again nine minutes later by a desperate last-ditch block from Kim Young-gwon.
Sweden had been the better team for much of the game - and finished with 15 attempts on goal to South Korea's five - but couldn't beat goalkeeper Jo Hyeon-woo until the penalty.
"I don't know if it's the biggest win in Mexico's history but doubtless it is one of the biggest for sure", said 22-year-old Lozano.
Shin said his players were unable to build on the early momentum because they were too anxious about the Swedes' physique and got away from their game. He will escape compulsory military service alongside his teammates if they make the podium this tournament.
Shin said the lethargic performance against Sweden wasn't for any lack of trying, but the task doesn't get any easier. "It was unfortunate we lost", he lamented, saying he was now focused on the next game against "formidable" Mexico, who stunned world champions Germany 1-0 in the other Group F opener. "Yes, that's why we did that", Shin said. "We have to regroup and focus on our next match in a few days".
Andersson said his team needed to learn from Mexico's success against Germany and be bold and attacking. "We are looking forward to the match. we have had excellent preparations". "I think they will be tough to play, but I also think they'll play a different style than they did against Germany".
"We really wanted to win this match".