Good news (she said cautiously) after being very wobbly and actually wanting food but refusing everything, Sammi actually got back on the bed and had a nap, then after giving me some purrs and snuggles, she was much steadier when she got down and ate with appetite. Not the normal amount but she gave it a good go.
I’m much more hopeful now - earlier on I thought I was going to have to phone the vet tomorrow and have the ‘is it time?’ talk.
Crossing fingers for continued improvement!