Why does my nail turn blue?

Both times when i took the SAT's and ACt's, while i was taking my test, i noticed my nail started to turn very blue, but when i finished it adjectives and walked around, it go back to usual. what does that mean?Why does my nail turn blue?
maybe due to some anxiety, but your hands be getting poor circulation. the term is cyanosis and usually occur around the lips when someone isn't getting ample oxygen. if it was a one time entry, don't worry just about it. but if it persists, move about get checked out.
btw, how did you do on the interview? good luck within college!
Sounds like you oyxgen level are low when you sit for long periods of time. I would see the doc and achieve this checked out.
you're cold or were immensely nervous??
you suggest, "why do my nails turn blue" , not "does"...anyway,it's poor circulation probably dance get it checked out by a doc:)