Siobhan, please be alert to your physical symptoms. Probably just coincidence, but there have been a few people on the forums who have had significant health 'episodes' of various types three of four weeks after switching to a healthy diet. Pebbles is the first one I read about, and twice since reading her experience, I have read someone else's journal and thought, 'hmmm, three or four weeks in, just like Pebbles.'
It makes me feel that as we start healing our bodies, things get 'shaken up' inside, and sometimes there are some negative consequences. Of course, this is completely unscientific, just a feeling, but as soon as I read your post, I thought of it, so I felt I had to say something. Please take care. If only to humor me.