Tbh, I find that kinda...like, autoflower hemp-looking.
Your watering, environment etc is good, something about either the genetics or your soil is really off.
And I don't mean to be rude, coz I've grown lots of crap, but I wouldn't grow that. But hey, I stay FAAAAAAAAAAR away from any ruderalis so I'm not exactly relatable, when it comes to that stuff.
I'll try to clarify, and explain what I mean. Like I've grown an enormous amount of strains and plants in varied outdoor conditions, winter or summer, doesn't matter. So i've seen a lot of shit, environmental effects, soil fuckups, genetic rejects, etc. That thing looks like it was hormonally messed up. Already browning pistils, very immature heads, week 7, to me, looks like it is foxtailing heavily too (and foxtailing is NOT just caused by light or heat, nutrients and shit effect it too because it is a hormonal balance thing, from various factors). And I've experienced that sort of shit, quite a few times (though never ruderalis).
like 1