I feel tension in my thighs that makes me want to stretch

I'm 27, male. I do a sitting job, although I swim 4 times a week. I'm an anxious person.
About 9 months ago I had an exceptionally stressful period and ever since I've been very worried about my health.
In particular I have a "tension" in my thighs, it's like an itch beneath the skin, that is relieved only when I stretch the legs; even walking doesn't help. It sometimes goes away for minutes or hours, and did not interfere with my sleep so far, thank God. It doesn't seem to be getting worse.

I'm worried that this may develop into something more serious, like Restless Legs Syndrome, a neurological illness that ruins lives.

What do you think? Is such a feeling normal?