My last period was November 8th and it lasted 3 days and flowed normal…

My last period was November 8th and it lasted 3 days and flowed normally as before, while the next should start on December 4th, but instead it came very light and little on the 4th and only spotted on the 5th. Now I tested positive since January but am confused about the results of three different scans from three different hospitals within a week. One confirmed (13 weeks with EDD July 24th), (second 9 weeks 4 days, EDD August 24th), (third 10 weeks 4 days, EDD September 2nd). Please give your opinion.