Healthy Pregnancy after period

So I had my regular 5 day period and was having symptoms during it so I took a pregnancy test on the 5th day that said positive. 3 days before my period thou I took a test and it was negative. I went to doc to see if maybe It was a miscarriage happening. Which was a week and half later. Luckily, I was told baby has a strong heart beat at 6 weeks. Anyone else experienced this before?