Am I miscarrying?

Hi everyone... I have tested positive for pregnancy seven times and AF is due to arrive tomorrow. Yesterday I was feeling very off and concerned about miscarriage, I took another test and I felt like the positive line was lighter than it should be. Alll day I had on and off dull aching back pain and then a couple hours later, I started spotting... this was at 7:00 pm last night, it’s now 7;00 am and I have not experienced anymore bleeding. Is it common during a miscarriage to start spotting and then a day or so later to really start bleeding? I want to believe I’m not going to miscarry but .. I’m pretty sick about it... thank you