Cannabis grows according to the conditions it's given. Big pot with lots of room for roots (say, 5 gallons), big healthy plant. I'll bet the tap root for your plant has already hit the bottom of that pot.
Continuing on... good fertilizing regimen (see Primo's advice in #3), good growth. There are various other factors like training and air circulation, but really the one I'm wondering about for your grow is that they're under CFLs. If you have lots of CFLs (8-10) and they're bright and you keep them close (2"-3" away)--and don't forget reflectors--they can work great, but a plant will very quickly outgrow just a few CFLs (and BTW, LED light bulbs are more up-to-date technology and last longer).
Your plant will still grow with less light, but the quality of the buds is directly proportional to how much light you give the plant, and cannabis like a LOT of light. Time to do some light shopping? I have grown indoors and outdoors with lots of light and not that much light and believe me, you will be much happier with LOTS of light--it's the difference between a pretty green plant and a plant covered with big sticky buds (assuming again that your pot and fertilizing regimen are up to snuff).
And yes, ideally you really do need to transplant within the next couple of weeks. And that said, I need to go transplant my tomato seedlings!
(And everything you need to know for a successful grow (minus the BS folklore) is right here at GWE. Great site. GWE plus maybe a little YouTube viewing and you're on your way.)
