I had sciatica back in 1999 when I had a 10-day back spasm that kicked my butt! That was actually what drove me to go from ~210 pounds down to 156
Sadly I forgot how much being over 200 sucked... and now I'm back on the losing track - now I have another back issue driving me to do it... heh!
Anyway! In my case, my left leg became useless for a few days, not just weak. I had no idea how heavy a leg was until I had to lift myself off the floor by bracing myself on a coffee table and listing with my arms and one semi-good leg.
As the spasm relented, my leg gained strength... but I had tingling, numbness, pins-and-needles, and jabs of pain that made it go out briefly as it recovered. All I assume from nerves getting squashed by the vertebra/disk being pulled out of alignment.
I hope for you that it goes away on its own
But if you DO end getting "surged" - I can share that my mom had surgery for bad disks and after suffering through years of back spasms. Good news: she has not had a single twinge after that surgery healed up over 15 years ago!
Best healthy wishes!