TTC rainbow baby

I lost my son three days after he was born. My fiancé and I are ttc. We’ve been trying since I was 5 weeks postpartum. I’ve shown some signs of light spotting but no period. I took a test two weeks ago and it was negative I’m scared to take another one bc I don’t want to see it say negative. This was my today pregnancy so I don’t know if my period just trying to regulate or if I’m pregnant. Help please!