I like the Assurance brand, but like some other tests (ie FR, etc)) they claim to detect a pregnancy 5-7 days before AF is due. For one, they'd have to be 10miu to do this (and they are both 25miu) and also like PP said implantation doesn't happen until 7-10dpo anyway so chances of getting a BFP before 10-12dpo is very slim. FF says 13.5 days is the average that a person gets their BFP, so definately tested too early. Best of luck and I hope you get your BFP soon!