Thanks for all the replies - that's why I love this forum
I'm still not totally convinced that she is in season - maybe she's 'pre-season' if there is such a thing?
There has been no more blood - I did use some kitchen towel on her yesterday and no evidence of blood whatsoever.
I quizzed Adrian my OH re the first lot of blood and he said it was more like watery blood, like a bloody discharge. My friend at work has a cocker spaniel who apparently bled 'proper' bright red blood during her season.
Sorry for all the gory details!
I'm still keeping her on a long line in the garden and leash walking for now anyway. She is her normal perky self and just wants to play!