You need to get the polyp removed and sent for biopsy. If it is a small polyp, it can be removed as a minor procedure, and you may not need anaesthesia. If it a large polyp, it is better removed in the operation theatre, in case there is bleeding. You should also get an ultrasound of the pelvis, to check if there are any more polyps, prior to the procedure.
You need to see a doctor and start medication for your
thyroid problem.