Possible m/c and sch

Justine
Has anyone else had an sch ? 
I've been told to expect a miscarriage because of slow rising hcg
Yesterday I had a massive bleed with lots of clots and tons of pain. The pain was terrible. 
I've read that the sch causes similar symptoms though. I did just go running the day before (I didn't know I had the sch yet) and I know that can make it worse. 
Anyone have any opinions? Was it likely a m/c or sch bleeding ?