Hello, since this disease is from your childhood. So pl mention about the tests ( as blood, thyroid etc) which you had gone through. With this brief history we can say only one thing that you might have hyperthyroidism
. Since you feel very hot so perspiration is there hence a lot of water evaporates and you feel desire for water. Is there any nodules over throat area where thyroid situates. If some swelling is there pl note it and go through the test.Complete thyroid test are to be done as early as possible.Good luck.