Spotting 5 weeks 1 day

Freaking out because I had some brown spotting today. It has only happened a couple times when I went to the bathroom but I had a miscarriage last month and that’s how things started. I know my hcg levels were rising like they should but idk why now the spotting. Left a message for the dr but waiting to hear back. I have my first ultrasound Monday and the wait is killing me. I just want this baby to be ok. Need prayers and anyone else going through this or have gone through this and had successful pregnancy.