Agree with Apoc, Initial stretch was probably due to inadequate lighting. I’m guessing you started with small light and later bought a bigger one or something like that maybe?
The big problem I see is main cola on the plant is taller than the light fixture, how is she gonna load up with trichs using only indirect and reflected light? Look at your bottom pic, the main cola is mostly dark even with lights on.
Today’s pro tip is... plants go under the light not above it! Yes, yes I’m being a smart ass, hopefully you can laugh too and shake it off. We’ve all done stupid shiz - will do more again tomorrow too.
Seriously your tree looks good that’s a monster but raising light now would burn up top of plant. Live, learn and save it for next time around. That soil thing on 6 months feed, that’s only for normal house & garden type plants, weed is not a normal houseplant and it is a heavy feeder. Yes cannabis specific nutes will help. Big box stores have basic garden type fertilizer but they are not compatible with both veg and flower cycles needed for this crop. There are still ways to grow cheap but it takes a bit of digging and guess work since most here have tried and failed with standard Lowe’s or Home Depot garden ferts then moved on to cannabis friendly nutes.
Regardless - best of luck to you!!!