ALS, PARAMYOTONIA CONGENITA or PLS

When I was 25 I was diagnosed with paramyotonia congenita.  At the time it seemed to fit with the problems I had been having.  Now almost 25 years later, new symptoms arose.  I recently lost all use of my left arm and my neck became "stuck" in one position for about 6 months.  I am on baclofen (20 mg 4X a day), and flexeril (10 mg 3x a day) and because of a tremor in my right hand was put on sinemet 25-100 mg, but after one month was removed because of no change.  Now four months later (and 3 office visits later) bloodwork showing muscle enzymes being excreted in bloodstream; an abnormal emg; mri of the cervical area being negative; and unknown results for Anti-Gad Antibodies and Anti-Amphysin;  I am now experiencing a hoarse voice and twitches in both arms and muscle spasms in both calves and back of thighs.  There are some days when I can barely lift my arms and walk across the floor.  With the rapid decline of my health, I am wondering if it could be ALS, PLS or my original diagnosis of PC.