Nipples! Ouch!

Elsy
Hello ladies!
I'm not sure what's going on. But, I've had very tender nipples for 7 days now. My period is not until 4 days. And I think I may have taken a pregnancy test too early. I took one yesterday (5 days til period). 
One, five day before your period is that too early to test? 
And two, could this be a early pregnancy symptom???