Need some advice.

To young to tell if its male or female and leaves are probably crispy due to heat stress take that tinfoil down it doesnt reflect liight it creates heat

 

Paint the walls a flat white or get some mylar emergency blankets will reflect the light better

 

Ypur plant looks hungry aswell any nutes yet and are you checking ph just noticed them brown spots

 

Feed that puppy

 

Put it into flower when its half the size you want it some plants will double even triple in size during 12/12 I would personally veg it for longer do some lst and you will get a better yield and you wont have to worry about height issues look at my plants in my last thread I have lst two plants they are huge (bushy) and under 3ft tall

 

I have gone cheap on nute I use tomatorite very cheap but works great just start off with quater dose

 

Lol it is lst low stress training very easy to do you just basicly tie the branches down it gets the canopy even which means more light penetration wich means more yield and keeps the plant low short and bushy