What Can Cause Severe Pain And Fleshy Discharge With Purple Red Blood?

Hi I had sex a few weeks ago just after my period twice and I ve just had a baby 4 months ago I just started the depo shot again just had massive pains and passed a fleshy looking thing about 5 or so cm long along with a heavy purpley reddish blood. Any chance I could of miscarried or what is happening I m in lots of pain still :(