why is it sometimes i feel my leg like ants biting me, like i cannot move my hand or leg a while then i must move it slowly slowly so as not to feel the ant biting, that he feeling, it is something like if u never move yr hand leg a while, then we feel lke ant biting then we can't move a while. i must move bit by bit and shake my hand, or leg slowly than be ok. why? i am scared.is it no circulation of blood.