leg weakness is not typically a first sign in pd. however pd usually is associated with stiffness and slowness of the limbs and this may feel like weakness. if you have a tremor especially if it is in the leg i would be more likely to think about pd as a cause. other things to consider: pain can lead to favoring the other leg - and a sense of weakness. a muscle or nerve problem in that leg. a back injury causing pain in the leg or pinching of a nerve to the leg. a stroke - but this is not likely given that it is quite sudden in onset and you would have gone to the hospital not webmd. please consider an appt with a neurologist.
can you tell me if leg weakness is a symptom of parkinson's disease?