Pretty sure I'm having a miscarriage

On Friday morning I went to have a blood test done to confirm that I was pregnant, but I started spotting before I left the house. That night, I had a really bad cramp that went from my stomach to my back.

Saturday morning, I got a positive blood test.

Saturday night, the spotting started again, it was bright red and there was a tiny bright red clot.

Today (Sunday), I'm exhausted and spotting pink and brown and having to wear a panty liner. I've been cramping off and on all day.