It could be gyno nipples that are formed during puberty due to
estrogen(1 of the cause but might not be it).That one cannot be
helped unless plastic surgery is done or if you are patient enough
to wait for it to disappear(once puberty nears ending).
http://en.wikipedia.org/wiki/Gynecomastia
selected text only:
Gynecomastia (or Gynaecomastia)is the development of abnormally
large mammary glands in males resulting in breast enlargement,
which can SOMETIMES cause secretion of milk.
Diagnosis
The condition usually can be diagnosed by examination by a
physician. Occasionally, imaging by X-rays or ultrasound is needed
to confirm the diagnosis. Blood tests are required to see if there
is any underlying disease causing the gynecomastia.