How do I know if an IV catheter was left in my wrist after the IV was removed?

I had surgery July 3, the IV was removed July 4. It is now July 15 and a portion of the vein in which the IV was placed is raised, hard and feels like there is something in it approximately 2 inches long. It does not hurt in my hand, but the hard place is where the vein crosses on on top of the knobby little bone on the outside of the wrist (sorry don't know the name of that bone) is very sore, especially when I flex my wrist. I expected the actual IV site to be sore for a few days, but this did not start hurting bad until 1 week after the surgery. Is it possible for the catheter to have sheared off and still be in there? There does not appear to be any sign of infection at the area, it just hurts. If the catheter did shear off, how would that be diagnosed and/or treated? What would be my best course of action?