Noticeable Veins In My Breasts

I've been experiencing tenderness in my breasts for the last couple of days. Started out dull but has gradually gotten worse since then. Now they're pretty sensitive and I noticed today a prominate blue vein on my right breast. I didn't think much of it, but I started looking into it. A lot of people say that's an early pregnancy symptom. Glow has me to start my period in two days but generally I'm behind that by four or more days. My breasts never get sore before my period. I took an hpt yesterday and got a negative. Do you think I tested too early or it's my mind playing tricks on me?