She was sitting/laying down (can't remember exactly) on the rug and as she went to get up she wobbled and swayed a bit, as she did that, she sort of stumbled against a cardboard box. Touching the box seemed to spook her and she leapt in the air, as she landed she stumbled but then jumped in the air a couple more times, stumbling each time she landed. It was all split seconds really, then she looked a bit dazed (and very suspicious of the box!). She got on the settee afterwards, absolutely fine, had a bit of a sleep and still seems fine. She's walking ok, not limping or wobbling now. Very odd.
Thinking back though, a couple of weeks ago, she was asleep on the settee and as she woke up she sat herself up, and wobbled and swayed (like she felt dizzy) - I didnt think anything too much of it at the time, just thought its like us sometimes if we get up quickly and feel a bit dizzy - but now after tonight I'm not so sure.