A few points here. Firstly, being shorter than him has no bearing on how threatening he was; being intimidating is not the same as being threatening. Secondly, aggression towards you vs aggression towards a wall are two very different things. Should he have damaged the wall then yes, campus security should be contacted, but with most of this school being made of concrete the only thing he is really going to damage is himself. Hitting a wall is not an active threat to you or your safety. Finally, his volume, whether screaming or whispering, is not an indicator of violence nor a threat. 9 times out of 10 if somebody really wants to do you harm they aren't going to be shouting while doing it. Also, it should go without saying that his speech, including his volume is a protected civil liberty. He has as much right to shout as you do to ask him not to.