welcome to RIU
@Ivorydoom420
regarding stretch on your girls, here are some real-life examples for you:
in at: 12" and end of stretch: 37" that's a stretch of 308%
in at 5" and end of stretch: 18" that's a stretch of 360%
first example was topped, second example wasn't. you will find a lot of variations with the stretch not only with the strain you choose, but also how choose to grow the plant. so be mindful of your height restrictions in flowering. you'll notice by end of day 21 in flower, they're usually done with the stretch.
no worries on your seed not being from a seed bank; it will be a good learning experience. my last bean purchase was from midweek song (they're advertised on here with a 20% discount code you should utilize, it's a good deal imo) and the stealth was pretty good.
have you fed your plant at all--you're using FFOF, right? when you up-pot next, plant some of that stem in the dirt too. look on RIU for a thread about planting a stretchy stem.
...and listen to
@Gary Goodson's advice re: lighting.