What Causes Fatigue, Difficulty Walking And Jerking Of Arms And Legs?

My problem started two months ago. Tweaching of my left eye. I went to see my Optha and he said to apply hot towel on my eye for a week every evening. The tweaching decreased. I was finishing a report and could not stop working so it was a strain on the eye. For the last two months I had slept not enough. I also noticed that sometimes my knee gave way while standing. This did not happen often but I noticed. In early August we travelled from Philippines to California for wedding which inevitably brought more fatique and late nights. Then we went to Las Vegas driving. That is when I noticed last week that I had general fatigue, difficulty walking, and jerking of arms and legs. I felt that my hips and heavy. I travlled to Houston from Vegas by air. I am trying to rest and try to swim in the pool in the house. It seems the situation is slowly getting better but only slightly. I have still sluggishness in walking, low energy in my arms and hands, low grip and difficulty in walking. What do you advise.