Thanks Nancy. I`m inclined to think it`s something I have done but since I am able to log in now, albeit it takes me longer as I have to type my whole details into both sign in boxes now, it`s better than being locked out!
I don`t see anyone else asking about this so I guess it was me or my system that messed things up. When I went to type the first letter of my username `r` into the first sign in box, it usually opened my whole details and then I just logged in. So IE seemed not to recognise this on that day, which tells me something somewhere was deleted. Not sure how though....x