Is E.J. looking nuts, or what?

Yesterday, when Stefano talked to E.J. he looked absolutely like he was going over the edge. Are we, the viewers, to understand that he is crazy in the worst sort of way(a psycho killer maybe)? Being angry, which he has been before, is ugly enough; but that look he had was scary. I can believe E.J. could/would end up like Nick, taking pills and booze and stark raving mad.