I fasted for 4 days and then yesterday I went out to get lunch with my friend, and I felt fine right after I ate so that doesn't seem to be the cause. But shortly after I got home I had no appetite for anything, and when I try to sleep, I wake up every 30 minutes with a nervous/confused feeling. I feel somewhat nauseous but nothing over the top, and I have a bad dry throat too. And when I get up to walk around, I feel weak and like I have to sit down again.