Trouble with 88 cent Walmart test

Is anyone else having trouble with the 88 cent test? I was getting positives with the 88 cent test but I bought some more and their much more faint on them which leads me to believe chemical pregnancy but I bought a first response test and it was a good line on one of those, I’m still worried it’s a chemical though- I’m also late on my period. I’m not sure where to post them correct me if I’m wrong.