What your mother is experiencing is her reality within the context of religion, you don't need to be religious/Christian to relate to her on that level. What would seem to her to be demonic interference would be how we perceive things we have in our Lives that we don't want to be there. She calls it 'demonic interference', you might call it 'toxic/negative energies' for instance. Use 'Christian' words but use your own thinking.

Yes, you could well have triggered your mother's Kundalini - if Kundalini is what it is. Nonetheless, whatever name you call it there seems to have been something of a 'cascade' going on. At the quantum level we are creatures of energy and because we have mass we have an energetic torsion field around us. If you think about it you sense energies all day every day, like when your friend is feeling low and you sense it. Kundalini is no different from any other energy, it's just an energetic subset of frequencies.

Work with your mother on an energetic level, if you want to calm her down then don't think about her needing to be calmed down, that's counter-productive. Be calm yourself and let the energies 'infect' your mother. Talk to her gently in Christian terms, because they're Christian they'll resonate better with her reality and she'll be more inclined to listen. However, it's the tone of your voice (the vibes) that'll make the difference and not the words you use. Tell her that you'll ask Archangel Michael to protect her for instance.