After the first weekend of the 2012 Olympics, China leads all countries with six gold medals and 12 total top three finishes. The U.S. isn't far behind with 11 medals in all.

The first few days of the London games saw a few surprises, with world records being set.

A few Americans that were expected to take home the gold finished their events without even earning a bronze medal. Other athletes performed well after coming to London with little expectations.

Here's a look at the opening weekend of the Olympics, along with some of the biggest surprises and upsets thus far.

Yi Siling won the first gold medal of the 2012 Olympics after competing for China in the women’s 10-meter air rifle. Siling won by 0.7 points over Poland's Sylwia Bogacka.

Michael Phelps set a record by winning his 19th career medal.

North Korea's Om Yun Chol won a gold medal when he set an Olympic record by lifting 168kg in the clean and jerk. He competed in the 56kg category, meaning he lifted three times his body weight.

Jordan Wieber missed out on the chance to win a gold medal after she made several mistakes, earning a score of 60.032 in the women’s gymnastics all-around event. The defending world champion was the favorite heading into the games.