I have been through this personally. What worked for me was detoxing my body of junk. I cut all caffeine, sugar and any unnecessary foods. I got more fresh air, and I forced myself to be active. The biggest thing though was drinking water. It really sounds like your body is working really hard to maintain equilibrium. Make it easier on it by giving it the things it needs. If that means drinking water and taking some multivitamins do that. Yoga is good to continue, but if you are loosing the ability to focus it may not be as useful. Perhaps try hot yoga? Sweating might be therapeutic if any of this is caused by an infection. i know all of this will seem like a waste of time if you are feeling as bad as I did, but what have you got to lose by eating extremely healthy for a week or so? Good luck, and I hope you feel better soon.