Well, tonight a friend and I took a look.
We took the Rear-Driver wheel off to examine the sensor. Everything looked fine there...no breakage, etc. So, we tried Freddi'* idea of taking off a line to the air shock to let the air out. Air came out and the car sunk down to normal level, as expected. After connecting the line back up, I started the car. The pump kicked in and this time only ran for 3 seconds or so. I'm not sure if the car rose at all, but if it did it was a TINY amount. So, at least the sensor is not telling it to pump until it'* full. We put 3 wheels in the trunk along with my friend and when I started the car up that time, it did move (though still not very much). Interesting.
Perhaps the sensor arm was stuck from road grime? and jacking the car up to take that wheel off un-stuck it? We did put some penetrating oil on those joints after looking at the sensor, just in case.
Anyway, all appears normal now, but I will keep an eye on it.