Hi Mystery1,
I do think you are herxing. Take it slow, and be sure to detox enough. Being in a herx makes you feel miserable, you will need to take it day by day, try not to stress about your new discovered limitations.
Most of us have these problems when on medication.
I understand you about the headaches. It has been one of my main complaints the last months. I have had 'normal' headaches for 19 years now, every single day, but lately I developped migraine attacks and cluster headaches. They drive me crazy. I can't get rid of them, but if it is about that headache at the back of my neck, I go and see my osteopath, he takes away the tension that has built up in my back, neck and shoulders. Maybe you can try that?
Good luck, and hold on,
MarieLS