Thanks Doreen, that's a great help.
I think I probably do need iron, because I have heavy periods, my blood is sometimes too light in iron to donate and we don't eat red meat that often (too expensive and D not that keen on it).
I won't throw away my multivits with iron but next time I'm at the doctor's I'll ask them about the ferritin test (usual response of doctors seems to be 'go away and stop worrying your head about things') but I can still try.
You've helped me decide what to do and stop worrying - Thanks, I really appreciate it.
Jay