Gyan had the chance to win the match, which was poised at 1-1, with the final kick of extra-time after Uruguay forward Luis Suarez had handled Dominic Adiyiah's header on the line, preventing a certain goal.
But Rennes forward Gyan crashed his penalty against the crossbar and although he netted in the ensuing shoot-out, Uruguay goalkeeper Fernando Muslera saved two kicks and the South Americans won 4-2 to move on to face Holland in the last four.
"I'll bounce back, I'm strong mentally," said Gyan. "I had the courage to take the penalty, but that's normal, I'm the penalty taker. But that's not the game, now he (Suarez) is the hero in his country, the ball was going in, he stopped it and I missed the penalty. That's the way it is."
Ghana's Serbian coach Milovan Rajevac said that miss had given Uruguay an advantage in the shoot-out. "We had this penalty and the chance to reach the semi-finals but we didn't get it," he said. "In the shoot-out Uruguay had a psychological advantage."
Gyan would have joined Cameroon legend Roger Milla as Africa's record goalscorer in FIFA World Cup finals had he netted the winner but it wasn't to be. Ghana goalkeeper Richard Kingson revealed he and his teammates had been trying to support their striker.
"We were consoling him (in the dressing rooms), it's a game so we need to forget about it," he said before complaining about Suarez's actions. "You can see from the beginning that it's unfair on our side, the referee should have allowed the goal but he gave a penalty. It's very unfortunate but it's also part of the game, you have to accept it and correct the mistake next time.
"Many things happen in football but you have to understand that little decisions can change every situation and that happened today. If the referee gives a goal we qualify for the semis, but he didn't, he gave a penalty.
"I'm a little bit down but I'm also happy for myself. There's nothing we can do now, we have to take it out of our minds and move forward. I'm very proud of the team, it's a young team and even in our country no one expected us to get to this stage."