Can someone please explain to me how long anxiety can last. It's been going on for over 30 years, my symptoms are: fatigue, headaches, especially in my neck, shaking inside, dizziness like I am off balance, and my skin will feel like it's burning. All this can last for weeks even months, then I may get some relief for awhile!! I do take meds, but cannot understand why they don't always work. I have had numerous testing, everything is always negative. Please, I need some reassurance.