Feeling challenged when I sing the name of Kali

yes, take it slowly in the beginning.

Kali is a destructive force that creates space and destroys the patterns you no longer need, so this clearing or energetic detoxification can of course feel challenging at times, it is like taking a cold shower, it clears you up and shifts your energy.

The same thing can happen with any mantra, technique or any new energy input that transforms you.