SITREP:
Sorry I'm late - it went well, mostly. I walked right up to him before work, said hi, told him I wasn't really sure what had happened that night but that it was a bad day for me and I hadn't meant anything to be taken personally, and that our team is a friendly group who works together and helps each other out and if any of us want to switch aisles we just discuss it. He basically apologized, said he'd been on a short fuse since he'd been bumped from area to area three times already (just shows he doesn't know how things work with us. he didn't get 'bumped', he was the one trying to bump people from areas they've been working in for a year. as the new guy he doesn't get to claim an area, he gets the leftover areas that aren't claimed. tough shit but that's the way it is, unless he wants to specifically ask someone to switch areas with him. But I decided to not get into that.) and we shook hands and he said we're cool.
Which did calm my adrenaline down a hell of a lot, and he's probably just fine and it's water under the bridge for him but I still tense up everytime I see him and don't want to be anywhere f*cking near him. Once someone's set me off that badly it takes me a hell of a long time to feel calm around them. But at least I'm not in a total state anymore where I'm ready to jump him or expecting him to jump me, so we've probably taken the potential for physical violence out of the equation. And given a few weeks I'll probably get to the place where I don't get tense as hell around him.
Hopefully it's all live and learn.
I keep thinking about it and it's not like I haven't had the occasional snarly or bitchy person at work before and I honestly think, as much as we can try to overanalyze it, that what sent me into the deep end wasn't him or the situation itself but the fact that he came at me in an aggressive way, body language-wise. He came at me like he was f*cking ready to fight, and you just don't do that to me. You do not act physically threatening in any way towards me; it puts me immediately into a very feral zone mentally and sends my adrenaline through the roof.
In the end I don't really know what to do if a similar situation happens again, except to at least recognize what's setting me off. I really don't know how to talk myself down from the state I get into when someone displays aggressive body language, except to perhaps in similar circumstances try to tell myself that their only intention is verbal aggression, not physical violence. Was he going to try to attack me to get me out of my area? No. Was he going to follow me home and murder me over it? NO. It seems kind of ridiculous now. I guess I just have to work on again focusing on MOST LIKELY scenario, not worst case scenario.