Well, 10+ hours later and nothing. Maybe what I thought was a bit of the water sack showing was really just pee caught in her mucus or something?? Anyway, she's acting normal, no changes, up and eating her beet pulp/alfalfa pellet/grain mix right now in the paddock with Sheila. Bummer, man.
Checked her again this morning before heading into work...still mucus, up and licking her belly (both sides), very cranky, but no other signs. I'm at the office today. Maybe there will be a baby there when I get home...