I'm not too sure about that miscarriage; usually you would have a lot of pain with that happening. The clumping could be a release of the uterus, in chunks which can lead to a heavier bleeding. That is a problem where the lining of the uterus doesn't shed properly. See your doctor and discuss this with him/her.
I think you did have a miscarrige because normally periods are just blood. When you went to the bathroom you said it was blotchy . Well it was like clumps yup you did have a miscarridge that's wtt happened to a relative of mine
If you think you can be pregnant, take a home pregnancy test or just set up an appointment with your doctor to know for sure. Good luck