At 10DPO I took an internet cheapie and an FRER. I have never had an issue with the FRER in my other pregnancies. The strip was positive and FRER stark white. I was convinced it was a chemical. The next day I took a digital with the others and again positive. The NEW box of FRER negative at the same time. That day I found out my HCG was 35. I’m now almost 5 weeks with great HCG numbers and it just started to come up at 4 weeks. So don’t be afraid to get a second opinion on test😂