-.- Dude...Just cut them down...It's not even worth trying to grow those plants if your not even semi-prepared.
Do more research and try again..
You're just completely setup for failure right now.
1. Shitty soil
2. You have no idea what you're doing
3. The questions your asking, could all be answered in 20 minutes if you took the time to actually read an article or two.
Now to address your questions.
A.) No, Random bag seeds will not produce shitty weed. Only the grower can personally grow shitty weed.
You get shitty weed from, Low nutrients, improper lighting schedules, bad soil.
The seeds you got will be what ever strain you picked them from, It will share the same genetics as it's mother plant.
Personally, i've grown dank ass nugs from seed i've pulled from Mid-grade Seed&Stem buds, Shit you would pay 50$ for half an ounce on the street. ( Not brown dirt mexi weed, but green mid-grade )
It all depends on how you grow it man...If you feed it properly, and take good care of the plant, you can grow amazing buds.
B.) Like i said, just cut them down. You aren't prepared enough, You'd be lucky if they even make it 2 more weeks before dying on you.
Seriously man, take 100$ go to home depot, get some REAL SOIL, REAL PLANT NUTES and order some Auto-Flowering Seeds from a seed bank.
Auto's are perfect for guys who don't know shit about growing. It's like weed growing on retard mode.
Under 20 hours of light a day, you can yield a couple ounces per plant. And the best thing about Auto's....They're feminized, They dont have a Vegetative stage of their grow, and it takes like 2 and a half months from seed to harvest.
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So in short, Cut those down, Invest in some real material for growing, and try again. Cause those plants will die, unless you go out tomorrow, and get everything you need.
Read more on this website, watch free growing videos, learn everything you can about basic growing, basic cannabis plant life, their growth cycle, everything.
Trust me on this. It makes such an enormous difference when you start a grow, armed with knowledge and the proper tools to grow.
This may come off as harsh, or mean, but thats not the intention.
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NOW if by some miracle, you get everything within the week, this grow could still be salvaged and probably turn out nice.
A few Key points :
You can't tell the sex of a plant, until you've given it 24 hours of complete darkness to reset it's internal lighting schedule clock, and then let it grow under 12 hours of light on, and 12 hours of darkness.
It takes 2-4 weeks for Pollen sacks and Pre-flowers to start showing.
I'm 40 days into my grow, and i still don't know the sex of my plants, because i haven't switched them over to flowering mode yet.
Growing Cannabis takes time, patience, and genuine care for your plants. If you don't care enough to not use the right things for growing, you'll end up with shitty weed, or even worse, no weed.
I hope you read this, and take what i've said into account.
We're here to help you, inform you, and overall spread the knowledge and methods we know so that everyone can be capable of growing their own cannabis plants.