Go back to the doctor. I had the same thing happen to me in the space of a few months and had to have total removal of the thyroid.
You don't mention if you had all your thyroid out. It could just be scarring inside which can get a bit lumpy, but only the doctor will know by feeling it for you. Don't wait for advice from the forum. Best to get it checked professionally.
If only one lobe was removed, ythe nodules may grow at another one.