Ecstasy and finger movments/cramps

[teky-t]

SWIM took a few E's one night and had a very good time. However, he experienced some cramping in the fingers of his left hand, which didn't last very long but has caused him some reason for concern! They moved inwards on there own as if to form a fist and for a few seconds SWIM had no control of his fingers. SWIM is aware Ecstasy has an effect on the nervous system and muscle tension (mostly in the jaw) but he would like to know if this is a normal thing to experience with the fingers? And if anyone else has experinced anything like this whilst on E? Or is it possible another drug may have been in the tablets SWIM took?