Is it normal to watch the perpendicular line while walking?

Wherever I walk, whether in public or alone, I always pay attention to either side of me. This is because I know my feet should not be perpendicular to certain things - poles, other people, the corner of a building, or anything relatively thin to my step.

The imaginary line extends as soon as my foot touches the ground, and it moves directly away from that side of my path. I cannot allow the line to reach a near object, when avoidable.

I need to watch this horizontal line every time I step. It often results in randomly giant or miniscule steps, but I suppose that's what it takes. Is this normal?