It looks like you're losing light against at least one wall. Get better reflective material--get a mylar blanket from Wal-Mart or paint that wall flat white. Also--get your plant as close to the lights as possible. Drop $6 for a thermomemter/humidity meter at Wal-Mart, put it in the pot so it's near the light, and see what the temp is when you move your plants close to the light(s). Keep temps under 85 while doing both those things, and you'll increase your growth rate. But it looks like she (hopefully) is off to a good start.