I Swollowed A Piece Of Hard Plastic By Accident It

I swollowed a piece of hard plastic by accident it got caught and I keep coughing. So I forced myself to vomit and i felt better. 4 days later I startes to have black stools. Also had another episode of feeling a tickle In my esophagus. Went to er they tested blood, anal exam and nothing. Now it's been another 3 days and I took cough syrup for a hasty cough and cold I have. I started to feel extreme pain when any food got to my upper chest down asophagus. Right now I have a Lil chest pain and severe acid reflux that won't go away even with my meds omethprazole