Seedling leaves are discolored and starting to curl

Way to much water, You want to let the soil get completely dry. Also you have her in a clear cup. Roots don't like light. I would transfer her into something that blocks light and has lots of holes in it to allow your roots to get air. Roots need to breathe. No need for any nutrients until your 3rd true leaf node and at that point you should only be giving 1/4 recommended dose or less. Seeds have all they need for the first 2 weeks of life. I would add a bit of cinnamon to the base of your plant to prevent it from getting a fungus infection (damping off )