I would make an appointment and discuss this with your doctor. If you don't like or understand what you are being told, make an appointment with an endocrinologist.
You probably just have solid nodules, but they mean you need an ultrasound guided biopsy to check for cancer in the nodule. The 2.8mm nodule is large enough to have a biopsy. The US does NOT point to cancer, but they would probably like to get a sample to compare with future tests. Nodules most often do not go away, they may shrink, but if they get a sample now, they can compare that with future samples to check for changes. The only characteristic that could point to cancer is that it is almost entirely solid. If it had vascularity (which the report states that it does not) I would be more concerned, cancer needs a blood supply to grow. The chances for cancer are slim, say 5-15%, I would not worry too much, but do get the biopsy.