Help! Miscarriage or Not?

Hey everyone! We think i am about 5 weeks. I had my first dr appt today after finding out a week ago i was pregnant by a home pregnancy test. The doctor scared me by saying there is no fluid around the baby & it could be a miscarriage that has not passed yet. She wants to hear a heart beat by next week... (possibly week 6). I dont know what to think. I have no bleeding or symptoms of a miscarriage . But i do have cramping? Anyone have any opinions on this?