Miscarriage

Trigger warning.

How can the doctor tell if you’re going through a miscarriage? Will they be able to tell straight away?

I found out I was pregnant a few weeks ago, now suddenly I’m experiencing extreme cramping and a lot of blood. What would the doctor need to do to be able to tell if I am or not? (Doctor, not hospital. I know a scan and internal camera etc) I’m petrified of doctors - I sound ridiculous. I’m going to go either way I just want to know what to expect. I’m so scared.