Okay so I keep getting these muscle spasm in the backs of my legs, which i've been told is from malnutrition, but i'm also getting them in my chest and my stomach, along with sharp pains, and what feels like a stitch in several places. These last a long time. Yesterday I ate a small meal and it happened for a few hours after that, whereas today I binged and purged and I have it all now since I purged, so i'm not sure exactly what it is. Has this happened to anyone else? And why does it happen?