Right leg weakness, increasing every few months.Please help!

I am an 18 year old male and first discovered weakness in my right leg when I started to experience tremors and unable to keep balance when standing on only right leg. Few days back when I woke up I discovered my lower right leg had become weak as compared to left leg and right knee was also feeling weak.Please give me a solution.

suggest go doctor or ER,.      could be many things

Got a ct scan done, came clear.