what made you suddenly start examining your crown? have you taken closeups of it before? most likely just a swirl.
From these pictures I don't think you have anything to worry about. I can't see any thinning, just the regular "swirl" of your vertex. I'm sure others will chime in and give you their opinions, but what I'd suggest is maybe taking pics every month or so for a while just to be sure.. but honestly, I see nothing to worry about.
Really appreciate it. I'll keep an eye on things monthly. Trying not to get paranoid. It's just most of my relatives on my dad's side go bald in that area. Plus a lot of my peers in my age group are starting to have or have had hair issues.