possible blood clotting disorder

Ash
I've had several miscarriages and the last one the doctor saw several blood clots in all three sacs I did end up miscarrying but dr is thinking I have a blood clotting disorder. She asked if I bleed heavily on periods (I don't it's mostly clots) if I'm tired all the time have a hard time losing weight etc. I'm supposed to get testing done next week but have to wait until my levels are zero. 
what exactly is going on? What do blood clots have to do with being tired? Can anyone fill me in I don't even know where to start.