Hi, I Just Stopped Taking My Pill And I Had

Hi, i just stopped taking my pill and I had pretty much no bleeding for 2 days today was very very heavy and I passed a large thick fleshy thing I felt really bad cramps just before Im 24 and have never experienced this before, I'm just worried what it is and should it have come out? It wasn't a blood clot as I have experienced those before this was a chunk of flesh. Thank you