I was trying out my new made Key, every time a different dose. (not really relevant)
Upon smoking a very small dose I felt a strange heat-up/feeling in my head.

Closest thing/experience I could compare it with:
When I'm going to eat an apple or pear, and I'm not sure if they're going to be sour or sweet, I'm going to expect neither of both,and still expect both (same for sour candy). And then when biting the apple to find out it's a damn sour one and your mouth get's a "stingy" feeling throughout it. Like a shiver throughout my mouth.

Well I get that feeling in my head/brain-area when I smoke a very small amount of dmt, but a little more "rise in temperature-like " and persistent.

What is it doing up there and on what areas are you working?

Warm tryptamine fingers creeping up into the occipital lobe triggering the welcome into sensory departure.

-Ask it!!

I'm sure it's a physical reaction somewhere. It's not a hallucination

I'm not in your body, so I can't say, other than you'd be surprised. I've had quite physical interactions with what seemed to be external energies along with what feels like "energy hotspots" being activated in my body. I'd rather not get into the semantics of whether what's happening is hallucinating at all, but your sensations could be psychical for lack of a better word.

That's just the DMT entering your blood.

So I'm the only one with this feeling w a small dose?
I thought maybe others had such experiences.