Pregnant!? and with IUD

I was expecting my period Two days ago. decided to take a test even though I heard of symptoms that the IUD slows down a period or stops it completely for a few months.. and I get a pregnant on a digital test . I just had the IUD inserted less than a week and a half ago... the doctor did take a pregnancy test the day of the insertion and it came back negative.. I'm excited but very deeply scared because I had a miscarriage this year in January period and now it scares me that I'm pregnant and with an IUD in me