So far, 3 people have been confirmed dead (although 70 are still unaccounted for), which considering there were nearly 4000 people on the ship is a mercifully low death toll (especially because it seems that very few lifeboats were launched), and doesn't say to me that 'mass panic' occurred. The ship worker interviewed does use the term 'panic' to describe people's behaviour as they evacuated, but other than saying that people were pushing, he doesn't go into any great detail about what they were actually doing. He also comments that people were unwilling to seperate from family members, which fits with Mawson's (2005) Social Attachment Theory, which says that in emergencies, people tend to stay with attachment figures and help them evacuate, rather than leaving the less able behind, which might be expected if people 'panicked'.
If any pushing did occur, it's quite possible that the rapid listing of the ship meant that people would have found it difficult to cooperate with each other, and may have accidentally bumped into others as they fell over as the ship tipped on its side. This incident may have some parallels with the sinking of the MV Estonia in the Baltic in the 1990s. Cornwell et al (2001) researched this tragedy, where over 800 people died, and concluded that the high death toll was due to people being unable to help each other because the ship went down so quickly, rather than because they 'panicked'.