It does seem a bit strange that you are gaining weight despite being hyperthyroid. The first thing you should do is to get your thyroid function tests
done from an independent lab, as more often than not the reports vary from one lab to the other. You should get the tests done in a fasting state (atleast 8 hrs of fasting).
Your hot flushes and loss of energy can even be explained because of your menopause
. You should even look for an alternate cause of your weight gain (diabetes
, obesity), as it is almost unheard of to gain weight along with symptomatic hyperthyroidism
I can see that your are very concerned about the situation but you need to be strong in order to overcome it. Hope you get well soon.