Pregnant straight after miscarriage?

Sorry theres a rant starting here!

I mc on 14th september. I was 6 weeks but my baby had stopped growing at 4 weeks or earlier.

I took a pregnancy test a week later.

On wednesday i did a pregnancy test, which came back positive (it was a digital).

I told my doctor i was pregnant, and he wouldnt believe me! He said its still old hormones. But i have told him my tests have gotten darker every day!

Now i dont know whether im pregnant or not!!!