Eagle eyes needed please!

St
Hi ladies I am wondering whether these internet cheapies are faulty and would love to know what you think please? The top test I took 10 minutes before the bottom test, but used the same cup of urine for both. The top test was dark by the time limit and hasn't changed since. There is a huge difference I think which makes me question whether this brand is reliable? What do you think? Has this happened to anyone before? Getting a false positive would be awful!! I am planning on picking up a frer test to use Friday if AF hasn't arrived. I am 11dpo and this is evening urine but quite concentrated I think. Thanks in advance ladies!!