Because you have diabeties
I gave blood for the 1st time ever today. I have muscle cramps in both of my feet tonight and feel sick at my stomach. I also wonder if muscle cramps are a side effect of donating blood.
because you are sitting on them, you are restricting blood from getting to your feet, so after a while you end up getting a tingling feeling commonly known as "pins and needles"!
Cardiac Circulation
Probably because the blood cells are flowing towards your hands/feet because they have been slapped or hurt or they're cold.
I guess your heart has stopped.
You do not actually get pins and needles in your hands and feet nor are they 'asleep'. What really is going on with your body is if you are in such a position where the blood cannot get into a certain part of your body, the hands/feet, etc will go numb. If blood does not circulate to all areas of the body for an extended period of time, the limb/limbs may suffer permanent damage.
loubethetric cancer
the blood in their body is deprived of oxygen and other materials in the vessels.
Sounds rather like poor circulation. Lack of oxygen in the feet (or elsewhere) could cause cyanosis, and that makes the skin look blue. When the blood supply has been cut off from, say, the feet, and then returns, tingling is sometimes felt.
If you have cold hands and feet, the blood is flowing to the core to keep it warm. The core is more important that the limbs. Put on more clothing.
If you're a smoker, it's because smokers have poor blood circulation, particularly in their extremities, i.e hands and feet.