Is it metal? in my eye?

Well yesterday I was benching, then I felt a sting in my eye. I took a shower, went to sleep. My eye turned reddish, and the thing was gone,(but I think its still there, it just turned black) and I went to the doctor, and said it was gone. He checked, and gave me med to lower the swelling. I got home and then saw the peice. It's not really doing anything, its just there, screwing with me. What is it?