Should I be worried?

St

So here’s a little history of what’s going on. I found out May 14th that my boyfriend and I were expecting. On July 8th we went in for a 4d ultrasound just to found out the baby had no heart beat. After going to the ER they confirmed it. On the 13th is when I started to lose the baby. The bleeding lasted for a week then stopped. I took a pregnancy test the week after to see if my HCG level went down, the test was negative. Last Wednesday I started having menstrual like cramping. That lasted two days then had very light brown spotting on Friday. It only happened once and when I wiped (sorry tmi). I took a pregnancy test Friday evening and it came out positive, very faint but the line was noticeable. I’ve taken multiple tests since then and all look the same. My history of miscarriages have me taking tests everyday to see if they get darker. I haven’t had a period since the miscarriage. But if I were to count my MC as CD then my period should arrive this weekend. Has anyone ever dealt with light BFP early and it ended up being a successful pregnancy?