Miscarried 7 weeks ago, dark positive test

Hi everyone, I miscarried 7 weeks ago at 6 weeks. I began to miscarry on May 5th and stopped around May 10th. I never went back to the doctor to check my HCG levels. Since I was so early the doctor advised to go back a week later to get an ultrasound to make sure everything was clearing as it was supposed too and it was. I didn't take a pregnancy test three weeks later because to be honest I didn't even know that was recommended. Since I haven't started my actual cycle I decided to take a test last week being 6 weeks since I miscarried and immediately there was a dark blue positive line. I took another test that same day and it said pregnant. A week later, which is today, I took another one and the positive line appears to have gotten darker. I'm so confused. I know it could be HCG from the miscarriage, but could this be a new pregnancy? I have an appt on the 13th of July and I just feel so eager to find out what's going on.