I had some similar symptoms and was diagnosed with depression, social anxiety and OCD. I'm pretty good in a comfortable environment with no stress but as soon as some pressure is applied I fall to sh*t real quick (get very edgy and act a little crazy). I avoided seeing a psychologist and avoided medication as I feared I would pretty much turn into a zombie (not literally) but after being put onto a mild antidepressant and seeing a psychologist my behaviour has improved immensely.
But yeah, some of your son's symptoms sound to me like social anxiety. Some people will fall in a heap under stressful situations while others will become aggressive. That's probably (well definitely) not the complete answer as social anxiety can stem from other problems but it might be a starting point.