I've been experiencing these head rushes for quite a while, now. I believe that they seem more severe than the usual, and even though I have been investigating them, no one seems to have quite the same ones as me, being that I have an extra symptom.
Usually, it happens when I am sitting, then stand. I stand up and instantly become dizzy, feel very faint and become off balanced. I normally fall down, unless I hold onto something. My vision goes black, and I feel my heart rate pick up. I feel semiconscious, like I've fainted but haven't at the same time. Then, unique to my case, right between my eyes hurts -like a brain freeze, or a severe headache- for a while. These "head rushes" mostly last for 1-2 minutes, rarely more. I eat and drink well, and consider myself healthy. I do suffer from anxiety, but I don't believe that is the cause. Anyone?