shaking, unable to sleep

Hi. On and off for the past month I wake up in the night shaking. My arms and legs shake pretty bad and just my whoel body. I try to go back to sleep but cannot because when I close my eyes I feel like I'm falling, and it scares me. So I read until I fall asleep reading. I don't know if this has anything to do with it, but for the past 3 months I am uncontrollably eating chocolate and candy and have gained almost 15 pounds. I am now 5foot 11inches and weigh 164 pounds. Also when I wake up I am really confused and almost paranoid and closing my eyes scares me the most.