Thyroid conditions are very very common. Mine has been "dying" since right after having my son. I was going for a few years every 3 months but now I typically go once a year. I am just about on a complete replacement therapy. I have one cyst...very tiny and not growing. Basically it will burn itself completely away! I use to be pretty upset about the whole thing but ya know.....in the grand scheme of everything ......its not that bad and completely controllable. Especially Hypo....it is the easier to manage and the least to turn out with anything malignant.
I would insist on a ultrasound of your thyroid though just to insure you have no lumps....or if you do that they make sure it isn't anything.