My first Grow

It is too wet, not sure what you are growing in. About a 30 percent course perlite woukd be helpful for drainage and reducing overwatering risk. Unless this is a coco grow. If coco the perlite is still good to have. But the issue would be ph, and nutrition

Whee bit too much light from the looks of it. back off slightly one way or another -- dim or more distance. Use resulting internode length (stem between 2 growth nodes) to dictate further adjustments to light. your cotys are yellow. you can fertilize at this point. the plant wants more than it is getting currently. if soil, start slowly and ramp up over time. take somenotes of what you dod and what happens. plant better next time. it's like learning to ride a bike --> just gotta do it. is that soil or soilles substrate? assumign soil. in future have better drainage properties. i don't see much in there. 50% of volume should be anything akin to perlite. large chunky things are less optimal, like chunks of wood chunks or actual large-ish twigs from god knows what that you sometimes see on lower quality soils. That shit will just rot and it impedes roots too much. smaller is better, but not dusty-small. Virtually impossible to drown a plant with this ratio. (70 / 30 for coco coir, need less because it holds less water per volume = same relative capacity at these 2 ratios.) It's agonizingly slow at first. once you get more 'real' leaves it speeds up greatly... you'll see it ramp up fast, soon.

Ok so she does look a little off color. First off what medium are you using, from the picture I would assume it doesn't have very good drainage. How often are you watering and how much?

cotyledons yellow because the nutrients within are pulled out by the plant to establish a root zone. That's why the first 2 weeks your seedling doesn't have much vertical growth. All the magic is taking place under the soil. I agree with everyone's assessment of your soil. There's no visible perlite in it. You need light fluffy, easy draining soil that will hold moisture but without being water logged. Roots need Oxygen and if they don't get itt he plant will be sad, droopy, anemic looking and begin to develop necrotic spots here and there. Light, fluffy, easy draining soil which is generally a 70% coco to 30% perlite ratio. When you prep your soil grab a handful of it and squish it in your hand and then look at it. Did it stay tightly compressed or is it compressed, but loose and easily breaks apart. When you plant a seedling in soil, there's no need to saturate the entirety of the soil. That water will just sit there forever and displace the space that could have otherwise housed oxygen. It's never a good practise to plant a seedling into a 5 gallon bucket. But everyone wants to grow auto's so fuck it do whatever. Apparently auto's don't take too kindly to transplanting. I wouldn't know from personal experience because i don't grow those stupid fucking things. Plants should be brought up incrementally by transplanting from a party cup to a 6" pot, to your final pot size. Transplanting usually pisses the plants off for 18 to 24 hours. You'll think you've killed them by how sad they can appear after it. That's pretty normal. Go to bed, wake up the next day and they'll all be perky and loving life! And they will grow rapidly with the new found root space. One other great benefit to transplanting is the ability to amend your soil with beneficial Fungi and Bacteria right where your will plop your transplants root system!

Absolutely fine, just a bit too wet. Forget about the condition of the cotyledons, they play no part in your plants' life once it has sprouted.

It is too wet, not sure what you are growing in. About a 30 percent course perlite woukd be helpful for drainage and reducing overwatering risk. Unless this is a coco grow. If coco the perlite is still good to have. But the issue would be ph, and nutrition.