How do you not panic over every little thing?

First time dad here and our baby has had a slight rash on his neck for like 2 days. I've googled it approximately 500 times and now I'm convinced it's either heat rash, a reaction to laundry detergent, eczema, or something worse. Called the pediatrician and they said wait and see. How do you guys deal with the anxiety? Every cough, every weird spot, every odd poop color sends me into research mode. Does this get easier?