You can have low dopamine production that is not yet putting you into the PD category. Personally, I believe lots of people are in this state and come out of it, if they are fortunate enough to deliberately or unknowingly start doing things that optimise their dopamine production capacity. Suggestions for how you might increase your well being:
1. Don't push for a PD dx just yet; it will trigger a drug protocol and PD drugs are not a cure, just a short term panacea that you will ultimately pay a huge price for in terms of side effects.
2. Decrease stress in your life, attend to anything you need to sort out in your work or personal life.
3. Look into learning stress management techniques such as meditation, tai chi, qigung, yoga.
4. Eat a balanced diet, fresh and unprocessed foods.
5. I would recommend trying Dopavite for six months. It is not a drug, just amino acids and vits, minerals at an optimal level for the production of your own dopamine. Everything in it is in food too, but this ensures the basic daily minimum requirements are met.
6. A lot of people with neurological problems are also b12 deficient so something like sublingual methylcobalamin, 5mg, from www.iherb.com
would provide coverage. Again, six months treatment should show a difference and won't cause harm. B12 deficiency doesn't get measured in a full blood count, and it can be masked by taking folate. There is also controversy about optimal levels. I try to keep my levels really high, like 1,000, given my problems.
Regarding scans and dx, the best the DaTScan can do is show cell activity/inactivity, rather than cell death. Whether the cells are dead or malfunctional is a source of some controversy among patients as well as the medical community. On top of this, there is quite a bit of 'photoshopping' in the production and interpretation of all scans, so be wary of definitive dx's either way.
There is also now a recovery movement of people who believe you can recover from PD. Google Bianca Molle, Howard Shifke, John Coleman, and Dr Robert Rogers who has highlighted their cases.
Good luck in your recovery. I too live in Ireland, btw.