Talk about being let down

So I am 3 months post partum. Hadn't gotten my period yet, no I am not breastfeeding anymore. So I decided to take a pregnancy test. And goodness did it come back positive. Well my dr is an asshat and wouldn't listen to me for lab tests. So here I am at the time 12 tests deep. 9 say positive 3 say negative. Finally he puts in the labs I asked for blood he puts in orders for urine. Almost a week goes by and nothing from my dr office. I take 3 more tests all say positive but my line is getting lighter. Results are in...negative. But why am I still getting positives, granted they aren't blazing but I have no idea when implantation happened since I have not had a period to track. Well last 3 tests 2 were almost negative and last one read no. I wasn't trying to get pregnant again so early but I am getting the marina because my ob says another pregnancy is going to have a lot of complications because of my age(34), weight (seriously overweight), and gestational diabetes. But still hurts my heart to basically watch it digress.