Firstly, your stem is that long because it is stretching for light. The sunlight you get through your window isn't going to be enough for it. You should get yourself a couple cool white CFL's and start from there.

Cutting off the stem will kill it. No leaves will grow back. And with the kink, I'm not sure its going to survive at all, since its so young. Its worth a shot I guess but you really do need to get some lights and get them close to it. Within a couple inches, but not touching it.
TheGanjaKing420 Reviewed by TheGanjaKing420 on . stem issues This is my fist time trying to grow. So I did some reaserch, and picked up a few things and decided to start with some seeds that I had lyeing around, for practice before I spent any money. Out of the 6 seeds 5 germinated, but 2 died within the first week. The other 3 seemed to be doing realy well. My concern now is that one of the plants is about 6 inches tall and the stem is still realy thin. I have steaked it up, but it got nocked when I was moving it to the window for some natural light, Rating: 5