Drooping leaves and purple underside of leaves in seedling. Pls help!

You are using too big pots! Therefore overwatering is garanteed! If your roots are dying purple is the sign your plants using up more Mg as the roots can supply it. I can't explain it like this guy so head over to the grow boss-> www.youtube.com/channel/UCIr3U1IcBrdO073_e-JJr6A

And I would cut off those peat moss cups you have them in before replanting them. I know you are supposed to be able to plant them directly in the new pot but in my experience early on in my growing I had very poor luck with those. I stopped using them all together after the second time. Every one of my plants I left them on died. Just a heads up... lol

Too much water, give it only when the pot is dry ✌️🏽