Sneak peek test

I did the sneak peek test around 10 weeks and had gotten inconclusive results. They sent another test. I did everything exactly the same. I made sure to clean and scrub my arm very well. I realized I had been wearing my sons jacket that day but I believe it was washed since the last time he wore it. Anyways, we received the results and came back as a boy result. My husband has researched and came across a lot of false boy results due to male contamination. I have a total of 3 boys, my husband and male dog that lives at home. I have an ultrasound this Friday and deep down I was confident we would be getting our baby girl this time around until this test. A healthy baby and pregnancy is what matters but this is our last. It’s hard to imagine life without a daughter. Anyone else experience something similar?