5K by accident

I have a 5K to run tomorrow morning.  I hadn't planned it and was, in fact, trying to avoid official organized runs for a while.  I seemed to have failed as I am registered for the run tomorrow.  It happened entirely by accident.  No really.  I was talking to a co-worker about an issue and the subject of this 5K came up.  When asked I said, No, I hadn't registered.  It just happened to be company sponsored. 
My co-worker said she had seen a note that they were needing another runner to fill a spot when someone cancelled.  Did I want to run?  I didn't think anything of it.  I shrugged.
Sure.
I was planning on running Saturday morning anyway on my own.  I also thought someone would have already claimed the spot.  My co-worker sent a note back that I was interested but someone had already filled that spot.  Then I got a note from the person organizing the run for our company.  Someone else had dropped out last minute and would I be interested?  I shrugged.
Sure.
There it was.  I was registered by accident.  I didn't do anything except maybe talk about running and then say sure.
Sure.
Maybe I should stop shrugging.
TT