Hyperthyroidism or hypothyroidism?

I had a blood test done and my ths level is low. The dr. said that i have hyperthyroidism. I have look at alot of info on this and I do not have any signs that they say are ociated with hyperthyroidism but i do have alot of symptoms that are ociated with hypothyroidism. I have gained quite a bit of weight and no mater how much sleep i get I am constantly sleep nad i always feel really cold. I keep my heater on 80* and i also wear a coat at work in my office. Can some one help me please?