Light Burn or Overwatering?

It looks like in all the photos in your diary the plants are very saturated. Maybe it's coincidence or you take your photos right after watering. If you're keeping it like that all the time then you're watering too much. A small plant doesn't drink very heavy and unless you have a lot of evaporation you probably don't need to water but once or twice in your first couple weeks in soil(based off the 2-3 gallon pot size mentioned in the diary). Try to learn to water by the weight of your pot. If you have a natural tendency to overwater, you could also consider coco in the future. That's a substrate you want to water frequently.