Bleeding

Has anyone bled and had a successful pregnancy? According to the doctors my levels are going up. I have to wait until next Friday to get a ultrasound, I went to the ER this week and said they had seen nothing but I was 4 weeks so it was probably too early. I’m really anxious and I am trying to stay calm. I’m not bleeding much now just spots of red blood when I wipe but not much blood comes out. I am hoping for the best, but I don’t know how to stay positive even though my doctor said that this could be a normal pregnancy.