Hi, I experience giddiness ,nausea , heavy head and a slight headache all at the same time. This feeling has begun to come and go . When it comes I feel I cannot concentrate on the work at hand. I also feel drained out and tired. The headache starts at the top of my neck just before it joins the head . I had been to a physiotherapist before however the exercises have not helped so far as the feeling keeps coming back. help !