The glans are connected to the CS, not the CC, so not seeing massive expansion of the glans is an indication that the CS is not being restricted at all and it probably wants to be restricted a little. So, OK, you are focussing on the sides but the grip needs to be tight enough that it actually takes some effort to go up the shaft in 3 second strokes. So, very carefully, try tightening the grip to the point where you can move it up the shaft but after a certain point it won’t move anymore (I say carefully because this is a ULI and is quite advanced), then reduce the strength of the grip enough to be able to continue the stroke. Hopefully you now understand what is too much pressure and what is just enough.
Not a stupid question. It’s a matter of experience but you’ll get there. Jelqing is about letting just enough blood to pass back through your grip to allow the stroke to proceed.