This is normal for a thirteen year old boy. It is called gynecomastia and is due to a hormonal imbalance at puberty. It is part of growing up and will go away on its own as your male hormones become predominant.
not really...no
Yes he does :)
Nipples that are really hard are referred to as being taut. They can also be called stiff or hard.
TWEAK UM! When a woman is aroused her nipples harden. OR you could always turn down the heat cold nipples=hard nipples
No it does not.
yes
No
It feels really good.
There are many things that can cause girls to have big nipples. The most common is simply just genetics. It also matters of the foods that they eat and if they have had a child or not. and if theyre really really really FAT
It really depends on the guy.
Really big huge breasts and nipples.
The number thirteen is a prime number, meaning the only whole numbers it is divisible by are one and thirteen. i really want to thank you guys