I was looking at my plant today and noticed some burn spots. It looked really bad under my grow light, almost like as if it was bird poop. Anyways it's only in a small area of my plant where the picture was taken. Is this something I need to worry about like if it's gonna spread? Is it really nutrient burn? I kind of want to cut off the leaves because I'm afraid this will spread. Any suggestions or should I not be so worried?