Spotting for 3 weeks, but period came on time with sharp cramps and heavy bleeding. prego?

I have had spotting for almost 3 weeks, basically since my last period, it seemed like it just didnt stop... but my period still came on time this month, just super heavy and cramps were terrible. Now I have stopped spotting/bleeding. I took 3 HPT and they come back hazy but positive, the line that makes it positive is super light. But other than the spotting and the cramps I had, I don't have any other symptoms of possibly pregnancy.... appetite is fine. No out of place nausea. No light headedness.... I have an appointment at planned parenthood for pregnancy testing within the next week, but am looking for possible answers or explanations before then... any help would be great! I feel like I may have been pregnant and experienced a miscarriage, which if its true i know its possible for the HPT to show positive if the hormones haven't gone down. Or maybe I am just pregnant? AHH I dont know, please help!