If it came up within timeframe at that time last may, it couldve been a chemical. If it came later on, it couldve been an evap. I use to get positive tests on blue dye and wasnt pregnant thats why i never get a blue dye test
What celestial said !!! Bc i am 5wks and i took one of those along with clear blue & first response and they give me my positive but as i check a few days to see my progression in all my tests this the only test where the line starts to fade out while my other old tests stayed nice and dark its very weak dye
I'd say it was a Chemical
Those tests make indents like that especially past the timeframe
Those tests SUCK