Leaves are curling down inward/ whats wrong with my plants?

my plant is about 3-4 months old and still in it's vegatative stage and the bottom sets of leaves are curling down inward [seem like the leaves are rollin inward] so i posted a question and then someone said that i need to flush my plants...... is this person trippin or is he right? to me it seems like it curling down because that bottom set of leaves is not gettin enough lights.... so what is it? Thanks

hes trippin its to young to flush. dose it have budes yet. post some pics it will help

what kind of lights u using