Hey there! Nice start! Your plant looks pretty healthy.
However, it definitely needs to be fed. I just looked up that burpee "organic" seed starting mix and it turns out it's just coco coir with a tiny bit of fertilizer in it for the first week. So the reason your plant is turning that light green color is because it needs nitrogen like
@Silentvirtue suggests.
Here's the thing though. Since that's coco, it's basically hydroponics because it's completely inert. Your going to need to pH balance your nutrient solution if you intend to use that medium through your whole grow. Here's a link to some more info on growing in coco:
Ever wondered how to use coco coir blocks to make a cannabis-friendly rich potting mix? This tutorial breaks it down...
www.growweedeasy.com
Conversely, if that's not what you were going for, you could up-pot into a bigger pot with a good organic soil and the soil would feed the plant for quite some time. Then you wouldn't need any additional nutes for a bit, and it's more forgiving on the pH.
The reviews for that Burpee stuff btw are 80% people being pissed off that burpee doesn't say it's inert on the packaging anywhere.