I start IV's all of the time in my job and am an RN. You have an infiltration. They knicked the vein when they stuck you and dye leaked out into the surrounding tissue. It is very painful. Stop what you are doing, get a warm wet towel, and a heating pad, watch tv, while you soak it. Take tylenol, or whatever you take for pain. The warmth will help dissapate the fluids. Expect tenderness for the next couple of weeks. Soak as often as you can. I'm sorry that happened. I had that happen to me too, after an IVP. It is very painful.