Possible miscarriage

Rhianon

I went today for my pregnancy exam and there test was positive but the sonogram shows nothing but blood. I had blood in my sonogram with my daughter at 3 1/2-4 weeks to but you could see her sac. We did blood work and more thursday. Wish me luck im so confused how can this happen

1st picture is this baby

2nd picture is my daughter

My last period was September 21st.