Check this plant out

looks like u have a pH imbalance, and also the leaves folding over and curling down is dehydration do to salt build up, pH imbalance can cause this, if the plant cant use the food do to pH lock-out, then the mineral salts stay there and can build up causing toxic salt build up.
whats ur medium? and pH at?
u dont have a huge proble on ur hands, to fix this just make up about 1 gal (or double ur grow mediums size),of ur normal nutrient straight, adjust to ur proper pH 5.8 hydro 6.3 soil (the range is 6.0-7.0 but i like 6.3) and water ur plant with the whole amount
with a bush like that u will get many tops, be sure to trim and leaves and small branches below the canopy, because most of the light will not penetrate down below, low light levels below the canopy will cause "larf" or small pop corn buds, if u trim them off when u see them start, the tops will receive more energy and produce larger buds
good luck

 

the canopy is the top half of the plant that shades the bottom half.

 

just start flowering it, it will do fine, u can keep it natural and when u harvest u,ll see the small larf at the bottom of the plant, u dont have to cut this off, its still smokeable, u can make hash or butter/oil with it.
the best way to learn is to do it! right?
so good luck with everything keep at it and u'll no ur strain after a few harvest (if u keep that strain going)

 

If your still worried about the canopy, try SCROG method. That will break up the canopy and allow more light to penetrate to the bud sites.