If you are seriously concerned you could go to an ER and ask for an x-ray. The thing will show up nicely. It helps keep from being brushed off if you use some key words like severe chest pain, shortness of breath, maybe being unable to swallow - but tell the truth.
The thing isn't supposed to fall off for a week. If mine hadn't fallen off by itself I was planning on going to an ER to have it removed, because the clinic had told me they wouldn't remove it. Mine hurt so bad I couldn't eat anything, could barely swallow a little water, the entire day it was on. But I've got a polio throat.