So my plant was doing just fine yesterday, im pretty sure i burned it by fertilizing way too early, i ended that. but anyways im growiung under cfl's and then jst getting then up to about six inches and then moving them outside... heres some pics. please help

Why is the stem changing color at the top?

Burnt?



Conditions...

The set up... (dont bang the lights, they work for what i need them for)





?????



Thanks everyone.