It Was 5w5d Since Missed Period. I Started Spotting And

It was 5w5d since missed period. I started spotting and light bleeding and went to er. Obgyn did an ultrasound and other tests and saw nothing except thickening wall. She tested hcg levels in my blood and asked me to come back in two days. I did and my hcg levels dropped. She said it was a miscarriage. On Saturday I began bleeding and passing tissue like a period and then for an hour in bad intense cramps every few minutes that got closer and closer together. Finally I passed what looked like a small empty sac. The pain is gone. Is that normal?