Targ said:
Is backache a symptom of kundalini being stimulated?
Could be, assuming it is only incidental and not permanent. I myself had several curbs with my kundalini where I would have weird back pains coming in waves for a couple of days whenever I tried moving my back but that was only for several days tops. My spine is healthy and fine so it definitely wasn't anything caused by some deformation or damage. The best I can explain this pain is as if something from inside of my spine was trying to stretch it and expand it.
If it persists for longer than a week though, definitely take a look at it at your doctor or something.