I'm not 100% sure if this is the same but historically I've often had something like a building itch in a muscle where I would feel a need to flex it as hard as I could, it would go away for a few seconds at that point and then start building again almost immediately - this could go on for most of the night or any time that I would sit still for two long.
For sleep melatonin and trying to get better hours has helped. I think part of the problem I had was being on haldol/risperidal with antidepressants for 8 years (from age 11 to 19), from that I ended up with akasthisia (which I'm pretty sure is what I still have now - though I'm not 100% sure if RLS is really a nighttime and lower body only version of it?).
If you can take melatonin try it. Otherwise, if you're on something like an antipsychotic, antidepressant, or anti-anxiety med I would start reading down the list of potential side effects. Likely its part genetic and getting off of or changing a med won't completely remove it but, it'll be a heck of a good start.
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The loneliest part of life: it's not just that no one is on your cloud, few can even see your cloud.