She's safely back where she belongs. She was probably hungry, cold, and terrified. Or maybe it was mostly a grand adventure. :-) She obviously didn't want to be picked up, though, luckily, after i saw her vanish under the bed, she coiled up by the nightstand on the other side, in what must've felt like a nice corner. (Snakes like corners.) I got heavy oven mitts.
One of the corners of her tank cover wasn't quite securely taped down, I guess. It sure is now! This could've been much worse; she could've found a way into the walls, or into the basement, or found a corner I wouldn't have found her in until it was too late. Very lucky that she just headed down the hall and found some furniture to hide under where I'd hear her slithering around. My heart rate and adrenaline are still through the roof.