I have been taking up to 4 bc powders a day for back pain and arthritis. I skipped them for two days and ended up in ER Fiday night with severe headache, vomiting, chills, and skin sensitivity. The docs really didn't know what was wrong as all tests came back negative. They opted for a migraine, which I never have had. Tried going over my prescribed meds and realized BC was the only one I had skipped. It's Sun. And I'm a little better but not much. Could it be withdrawal from BC? I don't drink or use unprescribed medication.