I was looking in the mirror and noticed my veins were extremely noticeable all of a sudden in my chest and breast its never really done this befire?

A bit suspicious: It is said here you are 21, so this is unusual. There is a condition called superior vena-cava-syndrome where the large vein above your heart is obstructed by a clot, tumor etc...Causing back-up of blood from above your heart level, thus causing the veins to bulge out. Don;t want to scare you, but you should get this checked out by your doc. Good luck.

Normal finding: I am amazed about how often I have women ask me about the veins on their breast. Occasionally they are spider veins but mostly they are blue veins. These are almost always normal findings and normal variations of chest veins. They tend to be more pronounced in fair skinned females and they may be related to hereditary factors or even pregnancies. No treatment is necessary unless for cosmetics.