Thanks Dave.
That is indeed true. I am very lucky to be able to afford to see Dr Forsyth, and only in my case because someone has given me some money as a gift to pay for it.
I have now had a whole range of blood tests done, and they have revealed some interesting things which I am waiting to discuss with Dr F in June. He has already sent me some useful sheets that relate to the findings.
I think it's helpful to have something to go on now, as I have been ill for 7 years, and some of the symptoms have got worse during that time, especially my stomach pain.