Answer:
Sometimes you feel it weigh a ton. Yet it is nothing, but somehow still there. Makes you uncomfortable around anyone, But speak its name and it's gone.
What starts with the letter T, is filled with T and ends in T?
He's small but he can climb a tower.
These are needed to finish a test
One might hang a locket from this
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.