I got the same head pressure feeling from Sulbutiamine too.I get energetic and positive responses from thiamine hcl, but it messes with sleep unfortunately. B6 also affects sleep, and I suspect riboflavin might do that too (although I haven’t tried it as a standalone supplement).
Sulbutiamine, I just found to feel like a more cholinergic version of coffee. It’s like my brain was tightened by one or two gears, but had that coffee ‘robotic’ like ‘pushing’ energy to it. It did feel nootropic, but I found the cholinergic feeling to induce a low mood. No mood enhancement for me. I read on schizophrenia forums studies quoted showing that D1 is involved in cholinergic/glutamatergic mechanisms.
I find stacking with Forskolin to up-regulate acetylcholine-esterase a viable strategy to lower acetylcholine and avoid the hypercholinergic state associated with low mood.