How do you deal with uncertainty about the health of a loved one?

My mother is supposed to get a melanoma removed in a few days. But they did an Xray of her lung, and found a “shadow.” So her melanoma surgery is delayed, while they take an MRI of her lung.

I don’t know what to think. I’m worried. A little scared. I think about my father. But it’s all what if, and I’m jumping ahead. What if it’s nothing? What if it’s a mistake in the Xray?

How do you… or how have you dealt with such situations where something deadly might be happening to someone you love? Do you freak? Do you calm yourself? Do you wildly catastrophize? What emotions do you have and how do you deal with them?