If she disappeared once she'll probably do it again so keep looking around for likely spots she might hide in. It will give you an idea of where to check the next time.
Something to watch for in addition to what's been mentioned is do you have a basement with a drop ceiling? The house I grew up in did and some of our Cats loved to climb up in there, we could never figure out how they kept getting in there so we eventually got rid of the drop ceiling and just dealt with seeing the bare wood.
I also had one of my Cats crawl under the dishwasher. I have NO idea how she managed to squeeze under there because it was like 3 inches of clearance, and I wouldn't have believed it if I didn't see her crawl out from underneath with my own eyes.
Something to watch for in addition to what's been mentioned is do you have a basement with a drop ceiling? The house I grew up in did and some of our Cats loved to climb up in there, we could never figure out how they kept getting in there so we eventually got rid of the drop ceiling and just dealt with seeing the bare wood.
I also had one of my Cats crawl under the dishwasher. I have NO idea how she managed to squeeze under there because it was like 3 inches of clearance, and I wouldn't have believed it if I didn't see her crawl out from underneath with my own eyes.