Positive Walmart brand and negative FRER???


Yesterday I got a vvvfl with a Walmart brand test. So today I figured I'd see if it got darker then take a First Response early Result. Well using the same sample from a cup, I got a definite positive on the Walmart cheapy, but NOTHING on the FRER!! What do y'all think??!

Note: I'm approx 10-11dpo. And both of these were taken within the time frame.