Quick glance

because of the light it is under, it looks pale but it likely is not... trust your eye more than the photo. I just clipped 2 leaves off my plant, i think i have similar diodes as your qb. When i took them out of grow area, they got much darker (not dark, just darker than under light) and healthier looking. So, if unsure, you can easily move it at this size. check under some cfl or incandescent etc. try to get used to what the correct green looks like under the light. at some point it's too big to move easily.

First signs of Too much nitrogen turns old growth dark green and makes the leaf blades claw up. Thts definitely not too much nitrogen! Too me ur leaves look pale. And I'd suspect too much light for the little girl to handle. Try bringing ur led panel up it's rather close to the little girl. Probably causing ur pale leaves.