Doug, I'm with you. I was fearless in high school and college when it came to doing anything on a car. Mainly because I was broke and had no choice but to do it myself.
Now I overthink everything and chicken out.
I remember rebuilding the front suspension on my '68 Camaro in the driveway when it was about 12 degrees outside. My dad walked out to smoke a cigarette, looked at the coil spring with the compression tool still cinching it up tight, laying on the ground and said, "Dont kill yourself!" and walked back into the house.