Blood Mucus Period Big Large 13 Days Late.Sudden Gush Of Blood.Did I Have A Miscarriage? Please Help?

13 days late.Sudden Gush of Blood.Did i have a miscarriage? Please Help? - blood mucus period big large

Last week I did a test and it was a weakness positive.Since Then I have 2 more tests and SA neg.On night I went through what looked like a blood clot a little larger thumb nail, covered with mucus and blood. Then bleeding.Sunday morning I stopped bleeding and started to leave, but heavy.I actually went into the bathroom and wiped and toilet paper seemed small pieces of thick black cloth covered with blood supply. When I wiped away the darkest material. Followed by very bad cramps worse and more frequent than normal menstrual pain. I had 2 and take panadine hurt.I Forte still hearing it from white or gray if miscarry.This was black, so I do not know what it was.
If I my period is generally higher for the first day, and it it.I am still very heavy bleeding and cramping and is 2 days.
Is this a miscarriage, do I have?
If anyone has experienced this.Could please help me understand.
Thanks