I have numbness in my limbs and occasionally in my hands what could be the cause?

Many possible causes. There is no way to determine without a more thorough examination and testing. While it sounds like it is neurologic in origin, all limb involvement makes this less likely. Simple things like hyperventilation or a low calcium level may cause this while other more serious autoimmune disorders or cardiovascular or central nervous system problems may be responsible but seek an evaluation by your md.