Levothyroxine Sodium and lifestyle

Started taking Levothyroxine 100 3 weeks ago, for last week I'm in agony, my joints and muscles are sore, specially legs and arms, got constant headaches, mood swings, I'm also short of breath which developed before muscle pains, went to the doctor, was told it's probably asthma (!!) got tablets and inhalator and he mentioned anxiety, when muscle pains started, went back, was told that it's not related with hypothyroidism or Levothyroxine, it's a virus (??) have to drink plenty of water and got Diazepam and link to anxiety website. Help, it's not stress related! I don't know what to do!! Does anyone know how to get rid of those pains?