I was diagnosed as hypothyroid about 6 weeks ago and have been on a dose of 100mcg. I go back for more tests to check the levels in a couple of weeks, but don't know what any of it means. I didn't know to ask for the results when I was first diagnosed and so don't know what they were originally. I know that TSH is thyroid stimulating hormone, but don't know what T3 and T4 means and what the right levels should be. Can anyone explain what they all mean and what I should be looking for?