Here's the update, and the answer.

I'm embarassed to say that the reason for all of the problems is that while I correctly drained the ATF from the rearward pan (although some say this is not necessary in a transmission flush, it IS the method described in the FAQ on this site), I thought I was draining the ATF from the return line at radiator in the front of the engine compartment...

HOWEVER I was draining the engine oil (!!!) from the oil cooler return line on the right side of the radiator, instead of the ATF cooler on the left. So misinformed. The 'engine oil' I thought I saw on my gravel driveway was ATF fluid, due to the dirt and gravel I couldn't see the redness. It was probably spitting out of the ATF dipstick line as I overfilled the ATF pan. The mechanic who helped me figure all of this out said that my transmission had 3 quarts extra oil in it! Thankfully, the overfilled tranny was only run for a block or two.

I'm a little bummed that my engine ran for a couple of minutes with very little to no oil, however, it sounds okay and at least I was simply idling in my driveway...Keeping my fingers crossed that it keeps running as well as it has been.

Note to self: make sure I know what part of the engine I'm dealing with next time I attempt to do something nice for my car!!!