1) Are you working too hard at this? Somatics is not "exercise."
think of the movement as explorations, not “exercises.” Imagine you are moving like seaweed not a tightly wound contraption, or working out. This can be a very different way of moving your body, if you come from a no pain, no gain mentality of fitness/physical therapy world. You are working with your nervous system. Treat it with care.
2) Are you not contracting both sides of your body at once?
3) Your muscles have released and can be sore after years of contraction
If you are releasing muscles that have been chronically tight for a long time and there can be soreness when they finally release.
4) If you feel pain while doing the moves, STOP.
I know a lot of modalities tell you pain is what is required to get rid of your pain. That is so wrong on so many levels! Pain causes tension. Tension causes pain. Explore tip 1 & 2 above and see if that helps. Or try motor planning the move. Or reach out and schedule a private, in-person or online session with me. Trust me, when you have some deeply ingrained Sensory Motor Amnesia, you might need a little outside help.
Let me know below in the comments below if you have questions.