This can have two meaning, either literal or slang. The literal term, means after birth for a males testicles to descend in to the scrotum. The slang, means for a boy to reach puberty (though this is phrase is misleading, because the testicles don't descend during puberty, but shortly after birth).
your balls dropping doesn't necessarily mean your balls drop it just mean your ball sac grows heavier and your voice breaks at the same time so people say your balls drop when you are at the main stage in puberty.
balls
this is really gross but a hobknocker is someone who hits guys balls
you don't
The dropping of balls and voice breaking both involve sudden changes in pitch. In the case of balls dropping, the pitch changes as the ball accelerates towards the ground. In the case of voice breaking during puberty, the pitch changes as the vocal cords grow and thicken, causing fluctuations in the voice.
That is slang for testicles.
It is said because the male normally has one testicle (usually the left) lower than the other. It happens once Puberty begins. Balls dropping is just a way of saying that the testicles have descended.
A fourteen year old shouldn't even see a guys balls. So, the answer is no
this kills sperm cells
Your question assumes guys' balls hurt whenever we are sick, which is definitely false. Any guy you know whose balls hurt them whenever they are sick should be urged to see their doctor!
Dropping balls and voices cracking
As hard as you can because some guys like to get hit there.