I've had pregnancy symptoms for 3.5 weeks, until Wed night when I started spotting. I did 2 HPT but both were negative. But I worked out I'd be at about 5.5 weeks preggers if I was. Spotting on Wed till Friday night, and then on Saturday I got a really really heavy and painful period, and of course is still going. Is this a miscarriage, even tho I had negative HPT?