I Get "spells". They Come On Suddenly Without Warning, And

I get "spells". They come on suddenly without warning, and happen 2 to 5 times a year for as long as I can remember and there does not seem to be a trigger, just random. I get tunnel vision and sweat profusely. My whole body get shaky and twitchy to the point I can't walk or stand. I have had my blood sugar checked, and it's fine. My blood pressure is great and other than these spells I am in perfect health. A lot of people in my family have the shakes but I am the only one who gets these "spells". Am I having seizures?