ok wait slow down. you have had a plant for EIGHT WEEKS and its only SIX INCHES? dude thats an issue. theres no way that plant is 100% healthy at 6 inches after 2 months. no way! my plants that are 2 months old are all well over 18 inches.
next: lets say the plant is healthy, usually, after 2 weeks, you see the preflowers and can sex the plant sometimes it will take 3 weeks,
but i dont think thats the issue. we need to see some more pics man. that 1 pic you posted... shows that its nitrogen deficient. thats probably why its so small. whats the dirt like? what are you feeding it? what light?
id stick it back on to a 18/6 or 20/4 schedule, and wait for it to recover and grow more. even if it did flower youd get maybe an eighth right now being very optomistic.