Umm???!!?

So I'm really late (over 2 weeks) with BFNs and last night I noticed a dark line down my belly. What is this? Called my doctor (who doesn't seem that concerned) and wants me to wait... I'm guessing time for a new dr. 
But what's with this line? 
Boobs have hurt on and off, not constantly, and had a few days of watery pink spotting which ended Sunday. 
Is it possible that my HPT is lying to me?!? Haha!