Hope your cat's better…..
sounds very like what happened to our cat a couple of years ago. She was about 15 at the time, just got off the chair and appeared to be drunk. Wandered around in very wobbly circles, even climbed up the stairs!
I was frantic, called in to work to say my cat was on it's last legs, got hubby home from work to help me get her to the vets.
By the time Dave got home about an hour later she was fast asleep, woke up when he went to her as if nothing had happened! Didn't want to upset her by taking her to the vet so we said we'd keep an eye on her and see how she got on, take her if we needed to.
Two years later we have a 17 year old cat, healthy as anything, just a bit deaf. We presume it was a mini stroke but she's still going strong and no sign of anything since.
Hope yours is a one off too.