Diagnosing Dystonia.

My Doctor has recently diagnosed me with focal dystonia in my left hand but another Doctor has told me it is most likely just  muscle cramps?  I am now completely confused.

My left hand goes into a spasm, not usually painful, but sometimes there is an altered sensation to the area affected, it will stay in this spasm from anything to a few minutes to about 15 minutes.  The skin pulls in on one section and looks all contorted, it all bunches up in another section.  I can not make this happen or predict when it will happen.  At present it is just happening randomly, once a week maybe, sometimes longer in between and sometimes closer.  I am right handed.

I have had my calcium levels checked and they are normal.  I am correct weight for my height, I am healthy, non smoker/ non drinker, 46 years old, I have had a probable diagnosis of Transverse Myelitis? but MRI has never confirmed this, I do have hyper reflexes on my left side, it is my left hand that is having these spasms. I have been having these spasms for about 5mths now, but they seem to be getting closer together but I am also experiencing some other painful spasms the last few weeks.

Can dystonia start in this way?  Would or could this just be a normal muscle spasms, it certainly doesn't look normal.

Regards,
Udkas
(Thank you in anticipation of your reply)