"I feel like I'm brimming with energy whenever I'm in a flushed state, that energy sticks with me long after it is gone"
Weird! I get a lot more energy from flushing from B3 but immediately after flushing I'm really tired. Like go to bed and sleep tired. If I take it in the day I'm groggy.
Definitely though it's helped with energy. I'm working out in some way most days. And good lord I'm actually starting to get some muscle tone in my shoulders and chest again.
I think I'm close to twice your age OTE, and been dealing with this for about 5 years plus some serious dairy and medium gluten intolerance. Also messed up blood sugars without it. Maybe the difference is in there.