Redonkulus like many stated above, and yourself, I had low thyroid and was fully diagnosed after 2 months of IP because I did not gain energy or any kind of "euphoria", in fact, I was so hungry and so tired I could barely function, like at 10am I would want to fall asleep on my desk. I am one of those "power through" people and looking back have no idea how I stayed on IP at that time, but I told my doctor/coach and they immediately said "you should not be feeling like that on IP" and I started thyroid, and felt immediately better.
After a few weeks of that I got quite a bit of energy and the hunger subsided. To be honest, I don't think I ever felt "euphoria" per say, and I think even on the thryoid, I had a little more hunger and fatigue than most people have, but hard to say as I can only compare by what people describe. I was also exercising somewhat mildly the whole year I was on IP.
I compensated by adding an extra IP packet or two whenever I felt I needed to through the day - I think I lost a little more slowly but consistently and am now easing into maintenance quite fine. I think the extra needed packet though was more because of the exercise than the thyroid.
I did try upping my thyroid dose a little at one point about 15 lbs from goal as I started to get tired and hungry and depleted again, and it was clearly too much - heart buzzing, etc.... so within a week dropped it back down and have stayed there without changing. I think at that point the depletion feeling was just my body nearing goal and starting to want more calories... but that last month or two was very hard for me, and I had to take extra rest time and cut back commitments. I'm not sure if that happened for anyone else here as they neared goal, I would actually be curious if it did.
But once I got into Phase 3 I was fine again.
p.s. Love your name by the way - I think it's probably my middle name - I have to shake my head sometimes at how redonkulus I can be
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