What do u think

Has anyone ever had issues with the signal first test at walmart for 88 cents? I have taken several of them on the past and I have never received any kind of second line. Not an evaporation an indent or anything. Yesterday I took a test. It looked negative. I stuck it in the cabinet and left it. I just looked at it again and this is what it looked like. I know you aren't supposed to read tests after a certain time limit but being that I have NEVER had this on any test I can't help but wonder. I plan on testing again with any frer tomorrow. My period isn't due until the 19th.