I hear you loud and clear. Exercise is meant to build muscle which weighs more than fat so you may be getting rid of some fat but staying the same weight. Looks like you might to have to cut down on calorie intake and make different food choices, I know I had to after menopause. One possible side effect of Euthyrox is increased appetite another is weight loss so who know what effects it's having on you? The Mediterranean Diet has lots of good suggestions and recipes all over the www. Good luck.
Euthyrox is a thyroid replacement medication, isn't it? Sounds like you possibly need an increase in medication. You should get current blood work done to make sure your thyroid levels are optimal for you.