I've had the weirdest, most unpleasant day. Went on a long hike with my family (in Asia so a few hours ahead) and felt terrible throughout, kept having these waves of what I can only describe as deja vu (everything is familiar, though slightly different, and I feel as if I've experienced it all in a dream before). Then the headache came on, still ongoing. Feel totally horrendous. Am home now and have taken ibruprofen which I'm hoping will take the edge off it. Anyone experienced anything like this? Any advice really appreciated, I feel so ill.