I run 3x150w cfl bulbs for 4 plants. The bulbs are really cheap, and you can run them through splitters on a light chord. I always get great results and only put about $75 into my growbox. With cfl bulbs, you can get those seedlings about 2 inches from the bulbs and it keps them short and branchy. My plants usually have about 3-4 nodes with branches forming on each node by 3 weeks.

It's way too soon for 12/12 man. Let those girls get some arms to hold their goods. You want your plants to branch out, or you just get one big bud with a dense tip and fluffy bottom from the immature bud sites. Give them some time, a good grow requires it. You can use some light nutes, like a 2-4-1 fish emulsion at around 2 weeks, assuming you aren't using MiracleGro. I start mine on the light nutes at 1/4 strength at about the size yours are now. Don't worry about the burn you have, feed them just water for a week or two and let them use up/wash out any extra nutes. Then you can start your nute regiment. And don't freak out when the cotelydons turn yellow and brown, and the first leaves dry up, it happens.