Can I still be pregnant?

Tee • Mommy to an angel baby born on January 22, 2014 at 20 weeks. #AidenLewis BFP 3/1/2015 BABY GIRL DUE 11-5-15
I saw the first positive hpt 4 days ago. Have been testing everyday. Then lines are not getting darker or lighter. I'm so confused! These photos ate the last three days. Today included.