Simon, it's my understanding that once you being treatment TSH is meaningless. In fact, many on these boards have their TSH supressed, pretty much as yours appears. What matters at this point are the Free T4 and FreeT3 numbers; these are your thyroid hormones (TSH is a pituitary hormone). Treatment should be based on FT numbers, not TSH.
The fact that you still have hypoT symptoms just reinforces this. If the doctor doesn't know this and wont listen I would suggest you find one who does. From your weight comment (stone) I suspect you're not in North America - I don't know how it works outside of NA but advice here is to seek out a naturopath or osteopath, a doctor who will treat the symptoms and not just the lab results.
BTW, those symptoms ARE associated with HypoT. Check out the information archive (stuck up top of this forum) for symptoms. You'll also find some good advice on which tests are needed and how to get them from your doctor - and how to interview a new doctor
Nat