What can be initial symptoms of parkinson's disease?

Tremors: Tremors in the hands at rest, problems with walking and reduced coordination in general are early symptoms.

Several Things: Before overt physical symptoms begin, one can experience pre-motor parkinson's issues: the most reliably reported 4 are chronic constipation, chronic depression, anosmia (part or complete loss of smell--which also effects taste appreciation) & rbd. Rbd stands for rem behavior disorder. Rem (dreaming stage sleep) can be accompanied by acting-out of dreams: talking, kicking, punching, running, etc.