All of my ultrasounds/scans came back normal but I have an enlarged thyroid, is that okay?

Probably. Unless the goiter (enlarged thyroid) is very large, it should cause few if any problems. However, something is causing the goiter. In the US, it is usually because the immune system is inappropriately making antibodies that attack a person's own proteins in the thyroid (auto-, or self-directed, immunity). This may cause abnormal thyroid levels in the future, and needs to be checked regularly.
U/S should indicate. If your thyroid is enlarged then the ultrasound report should've noted that when describing its size. If you indeed have an enlarged thyroid gland, then it isn't normal. Please discuss this with your doctor. Diffusely enlarged glands are often seen in patients with autoimmune thyroiditis in this country.