I can relate to your experience. It has been a little over a month since I became intentional about eating for heat. When I started, I was within my healthy weight range and a month in I still am (I think… I hope- I’ve not wanted to step on a scale), but I’m outside of my comfortable weight range. Initially I had to eat more calories to boost my temperature than I do now. Currently, I eat to appetite and make sure that every meal/snack I eat has some warming components. It’s not necessary for me to eat, let’s say, 600 calories of ice cream when I only need 200 calories’ worth to feel warm. And, I think it’s better to eat a smaller amount of calories if they’re very warming than a larger amount that doesn’t warm you up as much. I actually don’t count calories, though. Please don’t misunderstand me- I’m not recommending to cut calories down to the minimal, just that I don’t think you need to eat more than your body is craving. Matt did make a comment in DR2 that if your temps are low, you should make yourself eat even if you don’t feel hungry. (I don’t know what your situation is- is that how you’re feeling?) Experiment around and find what your body best responds to to warm up. And it’s REALLY helpful to cut the fluid intake.
I don’t know if any of this addresses your question(s), but I hope you can take away that I understand your concern and I think it’s good to be wary, like you are being. It’s probably going to take some time to reach homeostasis :/ I don’t like feeling thick and…blah about my weight, but I do like that I’m sleeping well, my mind is clear, my body is warm, and my pee is yeller :) Hang in there, when I was three days in I was not experiencing any of those things yet either.