Pregnant ? Or not pregnant

My husband and I are trying to conceive. However on October 24, 2017 we lost our DS at 20 weeks gestation. I bled for about 3 weeks and then nothing. My period began November 27, 2017 and ended on the 1st of December. After him and I had been having sex non-stop. Per the <a href="">Glow app</a> it said I had ovulated on the 11th of December so my husband and I had sex on the 9th and the 10th. Anyway, 2 weeks later, I decided to take 3 home pregnancy tests and they all came back positive. Could it be from the old pregnancy or could I be pregnant again. Mind you my period was supposed to start yesterday, but it has not. Please help .