Clen has nothing to do with thyroid. And if you just started tren, it probably hasn't had an effect on thyroid either. It's your diet. It wouldn't hurt to have labs done to check thyroid function, as you may have a pre exsting condition, but I'm pretty certain its your diet. Something is off, either betiween the balance beteen macros or the overall amount of calories. Keep in mind that you can't gain 17 lbs of fat in 1 wk. That just isn't going to happen. Its water retention. But it sounds like it might add to your body fat quickly at this rate. Assuming you were eating a clean diet while on clen, that was low enough in cals to lose fat, I would go back to that diet, asap and slowly reverse off of it, adding carbs back in slowly. Also, with a 17 lb gain, I would keep an eye on your blood pressure. This could be a problem with water so far out of control. 

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