alright, so let me give you a quick run-down. i started growing a plant with a desk lamp powered fluorescent light. i thought this might work, as to keeping the plant small: i had the light on a side of the plant, and rotated the plant daily. thus, the plant would grow back and forth towards the light rather than grow up. anyway, i just got a new light. it's a specific grow light, and it almost look like a black light. the light it puts out is sorta purple. and i just started using that this week. my plant is about 3 weeks old, has a few sets of leaves and is only like 4 inches tall... and just recently, the small round-ish leaves that are halfway down the stem (the ones that are there from the start) started to turn yellow and wilt. every other leaf is green and healthy, i believe. what is the problem here? or is it supposed to happen?