From Wikipedia
Stampede events that involve humans are extremely rare and are unlikely to be fatal.[5] According to Keith Still, professor of crowd science at Manchester Metropolitan University, “If you look at the analysis, I’ve not seen any instances of the cause of mass fatalities being a stampede. People don’t die because they panic. They panic because they are dying”.[5]
Paul Torrens, a professor at the Center for Geospatial Information Science at the University of Maryland, remarks that “the idea of the hysterical mass is a myth”.[5] Incidents involving crowds are often reported by media as the results of panic.[16][17] However, the scientific literature has explained how panic is a myth which is used to mislead the attention of the public from the real causes of crowd incidents, such as a crowd crush.[18][19][20] […] [M]ost major crowd disasters can be prevented by simple crowd management strategies.[22] Crushes can be prevented by organization and traffic control, such as barriers. […] Such incidents are invariably the product of organisational failures.[4]
The closest thing I have experienced was just after the barriers to the front section of a Pearl Jam concert opened. My girlfriend was standing in front of me and was actually lifted off the ground by the crowd momentarily until the people in front of her were able to move through the barrier. It was very scary trying to keep the people behind us from pushing us over and barely succeeding for long enough. And I’m not small either, crowd force is no joke.