Student goes wild

So today during my prep period I hear a student in the Hallway fighting with a dean , getting all physical. Im only a Sub but I noticed the dean was having a hard time restraining the student. Long story short I step out and help out, security arrives later on and takes this student.

I don't know whether I did right or wrong by stepping out. It's very scary to see how these students can actually hurt you. I was pushed and shoved but so was security and everyone there trying to calm this student down.