Is Mass In The Uterus Sign Of Pregnancy After D And C?

I had a d&c done when I was two months pregnant. I continued bleeding for 6 weeks. During these 6 weeks, I had sex again. When I went for a checkup they found a 1 cm mass which they assumed was due to an incomplete abortion. They put me on regestrone for 5 days and now the blood is very little and very dark. I just wanted to know if this is normal and if there s a chance that the mass is another foetus(if I got pregnant again)