Could it be miscarriage?

Patient: About 3 months ago, I started using the NuvaRing. I have been leaving it in for the full month to avoid having a period. About 2 months ago, I started spotting which then turned into bleeding which was heavier than my normal period. I also had worse cramps then I had ever had. About a month ago, a large amount of tissue was dispelled from my body when going to use the bathroom, it was quite large, about 3 inches in length. After this, the bleeding stopped within a day and no more cramping. Another doctor told me it was just uterine lining but I don’t believe that was correct. Could I have had a miscarriage?