Hello everyone ? I have such a problem, I'm very afraid, I'm pregnant …

Hello everyone ? I have such a problem, I'm very afraid, I'm pregnant 6 weeks, yesterday I felt discomfort in my lower abdomen and my waist was pulling (not strongly), then today I went for an ultrasound, they said there is a heartbeat, everything is ok. But they also said there is a contraction, threat. I booked an appointment with a doctor only for tomorrow. To those who had a pregnancy, a desired pregnancy, we really want a baby.