The best advice I can give you is to have it checked. My daughter just turned 22. She had the same thing. Imn her case it was a thyrod nodule and she had to have it removed. She is ok.
As you say it hurts, it is better to have it checked. Make an appointment with a otolaryngolist (ENT - ears, note and throat specialist)
My other question is, can you feel anything on the sides of your adams apple, or also above & below it?
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