Um, these experiences have been noted and documented for the last 100 years (or more). The body "runs" on a sort of direct current and, consequently, nerves and reactions can be triggered. Nothing to fret about.
Virtually every electrology text discusses this phenomenon. It's just "new to you." The DC (whilst working on eyebrows) can even create a tiny flash of light as the current stimulates the optic nerve. (People doing cataphoresis usually detect this effect.) No Problema!
Thanks for replying so quickly Michael! Such a relief to know that it's normal.
Btw I have started reading your book on blend method. Learning so much