8 weeks since last period. please advise.

Hey there. So it's been 8 weeks today since the last day of my last period. I took a hpt about 3 weeks ago and it was negative. This was after I'd been experiencing brown spotting on and off for about a week and a half. On one of my other posts someone said the discharge was my period, but can anyone explain why? I've never experienced this before. I did have a pregnancy that ended in miscarriage earlier this year and I'm not experiencing any of the symptoms of pregnancy that I did before. Is there still a possibility I could be pregnant, or does this signal any red flags for underlying disease I should be concerned about? I know ultimately I just need to see my doctor but anything you all can tell me will be great. Thank you in advance