" I have read it can have to do with magnesium deficiency, although have not tried to take any to see if it helps."

I was about to mention that. I used to have rather frequent muscle twitching until I added 200 mg a day of magnesium citrate to my supplement regimen. Now I rarely have muscle twitching.
Copper supplements may also be protective for nerves.

http://www.diagnose-me.com/cond/C542179.html

The dark rings around the eyes are classic symptoms of allergies. Molybdenum supplements, and detoxification herbs such as licorice root, milk thistle, and detox teas help to decrease these. Also drinking more water helps.