Well, my new tube hasn't gone flat, so I'm hoping my steel wire encounter was attached to a scrap of rubber, and just did a punch-n-run. With some of the noises I heard while crossing that debris-field, mislabeled as a bike lane, I wouldn't be surprised if that's what happened.
Thanks to my need to change tubes, I found out my hub wasn't rotating freely, so it needed rebuilt/regreased, as well. LBS mech said it was gritty, and just needed cleaned out. I still need to get a new chain, and eventually a new crankset... I am saving gas money. I am saving gas money. repeat mantra... sigh.