Davida, I don’t really think it’s “unhealthy” for the body to be burning protein when it thinks it has to. If one is really ‘starving’ and to the point where one is consuming one’s own muscle or other desired lean mass, then that’s a bad situation for most of us but I’d usually trust the body to do what it has to do, there.
On feeling less energetic, I really don’t know. I’ve never felt tired, personally, even when eating ridiculous amounts of protein. From what I’ve seen, it’s not that frequent that high protein makes people less energetic.
If one is fasting or eating well under their daily caloric expenditure, then if they’re not fat-adapted or are very lean with little fat to use, that would explain tiredness. There is the “thermic effect” of protein - as high as 35% of the energy in it is used just in the digestion of it. Makes people feel hotter, often, but I don’t think frequent tiredness is a thing there either.
Kidney problems might affect things when the kidneys are relatively burdened with getting rid of a lot of the byproducts of protein digestion and excretion. Just theorizing here - if the body is having trouble getting rid of the ammonia produced from protein breakdown and the urea (that the liver makes from ammonia (the ‘ornithine cycle’) because it’s less toxic than ammonia) then yeah, one might feel bad.