Why are these plants so sad?

On your diary it says you are growing in coco. Is this so? You also have perlite so although it looks like a prime overwatering I find that hard to believe. Have you got enough holes in the bottom of your pots? You don’t mention light distance , it may be that your light is too close

They are suffocated by saturated soil with no oxygen at the roots for them to breathe. Cannabis doesn't like soggy heavy wet soil. It likes soil on the dry side. Water only when your cups feel light when you lift them.

With the droopy leaves and the beginning of the yellowing of the bottom leaves, I’m thinking you have over watered your plants. I would let the soil dry out for a few days. They need to dry out in between waters. Typically at this stage it’s around every 3 days or till you can stick your finger down roughly 1 inch and feel it is dry. Another good way is to lift the plant up and tell how heavy it is. After you water pick it up to get a basis and then after a few days you should be able to tell by how light it feels. I hope this helps.

Looks like too much feed, and a over watering or underwater issue. Likely not enough run off If applying nutrition.