Welcome @cristian! Thanks for posting and good job on the filming!
I agree with @Pepepicks66 that this sounds pretty good!
One obvious thing is that your slow and fast movements are very different. The fast motion in particular is very flat: not all the upstrokes escape fully, so you can see in the slow motion clips that you occasionally “swipe” and hit an unwanted string on your way to the new string. Could this be the source of the discomfort you are feeling?
So one thing you can try is to make the motion slightly more diagonal so that the upstrokes escape a bit more. Just as an experiment you could try something like the “Gipsy form”, where the wrist is flexed and the motion can be a mix of wrist and forearm - which tends to create a more pronounced USX trajectory:
Out of curiosity, have you also tried these licks with DSX starting on an upstroke? How does that feel?