Is my plant dying?

This is my first plant so I don't exactly know what's wrong with it. I'm assuming it's over-watered but I know the leaves also droop down if it's being under-watered, how can you tell the difference between over and under-watering?

btw it's on a 24hour light cycle and I have not given it nutrients. The tips of the bottom two leaves are starting to get a bit hard and crunchy.

Your plant should be dead, not enough light get at least 2 more of those cfl's, 2 at 2700k red warm light and one at 6500k cool white, color, an overwatered plants will have thick plumb viens sticking out in the leaves with wet or damp soil, and under watered plant will have dry soil 1 inch under the dirts, and be limp or wiltered, always keep a temp, gauge and humidity gauge and small fan in there

Marijuana: Jorge's RX
http://books.google.com/books?id=WRNNS2TUB3YC&printsec=frontcover&dq=related:ISBN1878823272