A 38-year-old female presents to your office with chief complaint of fatigue and weight gain for the past 5 to 6 months. Her fatigue has also affected her performance at work, where she has difficulty concentrating on tasks. She recently began losing hair. She feels more tired than usual after work and has difficulty playing with her children in the evening. She did not have any of these symptoms until 6 months ago. She denies hot/cold intolerance. Weight has been relatively stable but she has gained ∼10 lb in the past 6 months despite attempting to eat healthy and exercise a few times weekly. She is generally happy and denies any recent mood changes. PMH is insignificant. The patient smokes five to six cigarettes a day and drinks alcohol socially. She takes birth control pills. HR 55, BP 120/80 mm Hg, RR 16, BMI 31. Physical examination reveals a pleasant female, oriented and appropriate. ENT examination reveals normal pharynx, no neck fullness, and no palpable thyroid nodules. Abdomen is soft, nontender. Skin examination reveals no lesions/rashes and there is no lower extremity edema. She donated blood last week and was told that her Hgb was normal. What is the appropriate next step in managing this patient?