Just to give some background info, 4 months ago levothyroxine was increased 25mg to 150mg and told to take iron tablets because TSH was 4.61 (0.4-4.0) and free t4 was 19.2 (12-22) and ferritin was 16 ug/L (25-300). Called the doc surgery today for latest blood results and receptionist informs me everything's normal. Well, I've never been normal (joke). So, I request my printout and wonder if this is why I can't sleep, have had heart palpitations and get anxious at the flick of a switch!! Free t4 is 24.8 pmo1/L (12-22) TSH 0.05 mu/L (0.4-4.0). Please help. Where do I go from here?