Evap line?

I'm one day late for my period with no sign of it showing up any time soon. So I took this dollar general test and at first I didn't see anything so I walked away and came back about an hour later and saw this. I know everyone is going to say that you can't trust it after the 10 minute mark but it just looked to strong and dark not to question. I ran water over it to see if the line disappeared and it didn't get any lighter. Just thought I would get some of your thoughts. Of course I will retest in the morning.