BPF first time ttc

AF was due 2/14. Didn't get my bfp until 18 dpo which was 2/18. This was mine and DH first month ttc so I was totally not expecting to see that second line! Here is the line progression.

First app with obgyn is March 8. Did anyone keep testing until your first app to make sure you were still pregnant? When does the rate of miscarriage go down? I'm 5 weeks and 4 days today and a ftm, so I'm just worried and trying to stay positive