Last Month I Had Two Positive Pregnancy Test, Went To

Last month I had two positive pregnancy test, went to the doctor because I started bleeding they did a vaginal ultrasound and the external, they say they didnt see anything and no positive blood test or urine. This month I had my period normal a little more crampy went to change my pad and I see a skin looking thing I ouput it alcohol to see if it disolves like a blood cloth but no it looks like a gut or something is about an inch long. I would like to know what it could be and what to do thank you.