Well hate to say this but bashman isn't right. It's not burn, you have a low nitrogen condition in your soil. In times like this I usually recommend people use Dynagro 7-9-5 as it is a complete fert, having the calcium and magnesium needed, along with the other nutes. It's kind of pricey as you get a rather big bottle for just one or two plants, but the good news is it will solve you fertilizer issues. Just follow the instructions on the back where you use 1/4 to 1/2 teaspoon of fert in a gallon of water. I'd probably go with 1/2 tsp as it looks like your plant needs a shot of nitrogen. The yellow on the lower leaves indicate that your problem is too little nitrogen in the soil, not too much. Just be careful how much fert you use in the future as you can easily overdo it. The leaf tip burn that bashman mentions isn't from the light. It's caused by an over-fert condition but as I mention, this isn't your problem. Flushing the soil will only make things worse. Give some dynagro fert from your local hydro shop and you'll see the plant green up in a couple of days.