Hi a369,
What you are describing sounds very much like what many people with breasts experience! Areolas and nipples change over time quite a bit, especially when we go through puberty and they grow. There is a lot of variation on the size and shape and color of the areola and nipple between different people. And the tiny bumps you are describing are glands called “Montgomery glands”!
Areolas and nipples change texture in response to touch and temperature. This can happen really quickly, like within seconds! When they are cold, areolas become more wrinkly. When someone is aroused, nipples may become more erect.
You can check out this article for more details:
Abreast: The Basics of Boobies