Cycle day 45 bfn

Hi, I’m new here. I’m on cycle day #45. My cycles are usually 28-32 days. I’ve taken numerous urine tests all bfn, I had bloodwork done 3 days ago again bfn. I have no signs of cycle or signs of pregnancy. Only symptom I’ve had is slight soreness in lower back that started today, occasional nausea that comes in waves. My dr prescribed me Provera to start my cycles, my husband wants me to wait it out, he’s hopeful that my hcg levels are just low. Has anyone else had this issue and resulted in a positive and viable pregnancy?