Did it come up within the time frame or after?
I completely stopped using these as they gave me so many false positives! They did look like that when they were false, just thinner and on one side. They're usually a bit thicker when it's positive, maybe try a different brand!
@Charlotte agreed. This looked like my evap line too
@Charlotte sammmeee!!
This is what my first positive looked like, then I took an early detection digital test which confirms the positive. I did another line test a few days later and for a very dark line