Muscle twitches can actually come as a result of Vitamin D. Try cutting back on vitamins that contain Vitamin D for a little while, unless you have a recent confirmed Vitamin D defficiency.
I had the same thing from multivitamins that contained Vitamin D, and it sounded weird that even suchj a low dose could do it, but somone told me, I tried cutting them, and the twitches are gone. Mine would be in the large thigh muscles, very uncomfortable, actually, but not painful.