I reopened Photoshop today, and my lines looked like right. I assume that restarting the program or my computer is what fixed it.
Your brush strokes show that spacing is set too high
And that you probably had some size and roundness jitter set
Exaggerated to make the point
For nice clean smooth brush strokes, use a fully hard brush with spacing set to no more than 5% (1% if the brush size is not too big and your system can keep up). Turn off all jitter, and if using Windows, get and install Lazy Nezumi Pro. If you use a Mac, have a look at Hej Stylus. It is very simple compared to LNP, but I assume it will at least help with smooth brush strokes. Anyone here use Hej Stylus and care to tell us how well it works? Thanks