Thanks for the replies guys. I think that you are probably right that I haven't noticed the bunions forming - I have been wearing ski socks and bed socks constantly since it snowed before xmas so haven't had a good look at my feet for a while.
I think that the bungions were more pronounced and quite red straight after yesterday's snow run as they do seem to have shrunk a bit over night.
I don't wear tight fitting shoes, but maybe my Nike Pegasus Goretex Trail shoes haven't helped matters. They are a snug fit around my toes, with less give in the material than normal trainer material. And all the off-road and snow running that I have done in them over the last few months may have causes additional foot stresses.
...... Actually I have probably put my feet through a mountain of foot stresses after runing for 28 years on rough surfaces!! One 2nd toe joint has already stopped working about 5 years ago.
Still the bunion's don't seem painful, which is good, and I can keep an eye on them now that I have noticed them.
Julie