/dev/zero

First I get sarcastic email for actually suggesting we could help another department get something done, then when I get to work today, my supervisor, “W”, has to “talk to me” at some point.
When we both get a free moment to step outside and talk, it seems someone has informed W, and the boss, “J”, of an incident where I “screamed” at someone yesterday about not doing their job and I tried to tell them what to do. Apparently I’ve been trying to boss people around, giving orders to people from other departments, etc. Funny, I must have amnesia. I have absolutely no recollection of ever having “screamed” at anybody at work, ever. And I have never attempted to give orders to anyone from any other department or otherwise tell them what to do, unless they specifically asked. The person at whom I am supposed to have screamed was even named. I haven’t had anything other than perfectly polite conversations with this person since… well since the day she was hired. Including today. We had perfectly normal, polite conversations today, with no tension or anything.
Luckily my supervisor and my boss, know me better than that and just wanted to get my side of it, which was that I had absolutely no clue what that was about.
It would appear someone is out to stab me in the back. I have no idea why.