Grounding and shielding or the lack thereof is not going to make a candle burn wonky.
So quick to jump and make much ado about nothing.
Grounding, is quite simply mentally grounding yourself to a solid object or place. I tend to "see", imagine, visualize (choose your word) roots growing from my body and achoring it to the chair, floor, ground etc.
Shielding is nothing more than mental shields to hide your thoughts. Some people use file cabinets shut and locked, some use walls, doors, curtains. My grandmother used mason jars and she buried them in the garden of her mind.