Is it normal that i woke up to different nipples???

I woke up to other day to larger nipples that have blue veins very evident going through them and look slightly deformed to me, also very sore.
Today is day 5 of my missed period and i keep getting a negative when I test.. What can explain whats going on with me boobs? Am I in fact pregnant or could this be something more serious?

thanks for any help!