FT4 does look a little high in the range, but not above most ranges. Ranges vary
lab to
lab and have to come from you own
lab report.
Your doctor should test TSI (thyroid stimulating immunoglobulin), which would tell you if you have Graves' or not. TPOab (thyroid peroxidase antibodies) should also be tested. They can be elevated with both postpartum thyroiditis and Hashimoto's thyroiditis.
A goiter is not the cause, but the result, of thyroid disease.