If you left it any longer than the time on the box, you can get a false positive. I’d test again with a pink dye test and don’t look at it past the window they give in the directions
It’s def positive . I’d retest in about 3 days to be sure.
How long do you reckon it was sitting there before you came back to it? If the instructions said to check at 2 minutes then anything that shows up past 2 minutes is an invalid result. Definitely just go buy one of those cheap red dye tests at the dollar store and retest.
I would take a second test since there was a time gap in between, but I definitely do see a line.
It looks much darker in person