Answer:
One by one we fall from heaven down into the depths of past, And our world is ever upturned so that yet some time we’ll last.
There are millions of me. I am very small but when moving fast I am deadly.
It can cause deflation of tires when dropped from the rear of spy cars.
Though easy to spot, when allowed to plume, It is hard to see, when held in a room.
It's anything but amusing when this body part gets hit.
A doctor might remove one from the neck of a Dracula victim.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?