That sounds like there is too much resistance when playing through the strings and may be playing too deep. Unless your primary motion is causing this.
I would also play around with the amount of edge picking you do, and if a beginner, I would argue it’s much easier to learn with a good edge picking angle even if you want to play flat at some point for effect. This is because it is much easier to develop a smooth fast motion with less resistance.
I did one lesson with Teemu a few years ago and picking depth was something he personally worked on extensively. Trying to reduce the depth as much as possible while not worrying about the actual width of the picking stroke. It helped my playing significantly, I play with jazz picks typically and so long as I have a sharp tip my picking depth is essentially 0, rarely going passed the underside of the string. It is also extremely consistent in this regard. I found this easier to practice acoustically.
It should take very minimal pressure to hold the pick, and your forearm should not be flexing. I essentially have no grip on my fingertips whatsoever due to chemical damage when I was younger, and still use very minimal pressure. In my case I do need to use extremely grippy picks due to this though.