Hi. I Have Had The Following Symptoms Over The Last

hi. I have had the following symptoms over the last few months- fatigue, depression, weight gain,and temperature fluctuation.My Dr checked my thryoid twice and the tsh level went up slightly but was not in the range for treatment but my dr suggested I try the synthroid to see if it would help my symptoms. Iam hessitant to do so, as I dont want totake a medicine I may not need. Any ideas what else might be causing these symptoms? my depression seems better now that spring is here , but I continue to gain weight , at least a pound a week for the last few weeks.