Get a video laryngoscopic examination done immediately.A small piece of plastic will usually be swallowed with no untoward effects. A sharp piece will usually get stuck in the abundant lymphoid tissue present in the throat. Many a times it is only the injury caused by the foreign body that irritates the throat. Plastic will usually not get picked up in an x-ray, however it a always better to get set of neck x-rays done. A barium swallow is also advisable if any swallowing difficulty persists.