What are the syptoms of a miscarraige?????

I think I’m having a misscarraige. I went to the hospital, but I started to wait so long that I ended up leaving. I wasn’t sure if I was pregnant. I thought I was and my period was going on three months late. I was bleeding really bad and had cramps so bad that I could barely walk. I was aslo passing large clots. I just want to know if what I was experiencing could have been a miscarraige.