To answer your original question, "What's wrong with my tomato plants?": It is most definitely sun scald, which someone else also pointed out. Take them out of the direct sun a little to let them recover and make sure to just give as much water as they need. Over-watering them after they've already been burnt might be their death knell. To address some of what was said here after that: Based on your pictures, the plants are slightly leggy, but only slightly in my opinion - the real issue you are dealing with now is that you put your plants into too much direct sunlight too quickly, and they need to recover from that before they'll do anything. I have seen some people who choose to grow seedlings on the windowsill without lights and they can turn out OK - not great - but hey, it's cheaper and if it works for you, no need to change it... everyone on here has their own opinions though. I choose to grow under lights and I sprout a month earlier than some and grow in the cooler conditions in my basement. That works great for me, but that has one primary disadvantage - the plants take a little longer to harden off to wind and direct sunlight... But hey, I'm willing to accept that cost since they are generally good stocky plants with good root systems. If you should choose to start indoors and grow under lights (which is recommended), you don't need to spend a fortune on lighting systems. I grow the majority of my seedlings under a jerry-rigged lighting fixture I got at a yard sale coupled with a florescent bulb I picked up from a local hardware store. No matter what you choose to do going forward, definitely check out the link that Dave provided. While growing tomatoes is far from rocket science, there are still some basics worth knowing before getting started. If you don't choose to follow everything you read, that's fine, but at least you'll have more to work with than before.

I love sans because they can be so forgiving. I put mine outside in the summer and when autumn comes I bring them back in. Because they've grown they sometimes have trouble fitting back on the windowsill. If a leaf is sticking out I'll just cut the offending leaf off near the base with a very sharp knife. It doesn't seem to hurt them. I think of them as semi-dormant in winter and they only get a trickle of water once or twice a month. Again, they do fine. Personally, while they are in this semi-dormant state I wouldn't repot them. The roots aren't really going to actively grow much in the winter so to disturb them might not be a good thing. Late spring, is when I usually divide or repot mine. Cactus mix ought to do alright. I have a blend of my own, but unlike many other cactus/succulents I've grown (and killed) they aren't as fussy about it as long as the drainage is good......Good luck with your plant. It's very nice looking specimen.......Maryl

A few hours of LED light each day is clearly not enough replacement for plants (like echeverias) that crave full to shaded sunlight. Mine winter with grow lights up to 8-10 hours a day on a timer, even that is not enough to replace what natural sunlight provides. I set them about 2-3 inches from the actual light bulb, so if you can, adjust your lamp closer to the plants. If you are worried about overwatering, get a small fan to ventilate, and make sure the water doesn't sit in the bottom. Plants wise, your plants are looking fine. As crenda mentioned, flowers wilt and dry away. The most important things to keep watch are how the leaves grow. Healthy roots and leaves = healthy plants.

Definitely time to repot. This so-called soil provided by the producers is not good in the long run. Try a mixture of lean soil (seeding soil works nicely), gravel (very fine, it may be very coarse sand), some seramis and perhaps a little pine bark. Or any not-too-rich soil with lots of perlite mixed into it. The trick is to make the soil very free-draining, then you may water with very little danger of overwatering. I think that wrinkling of the leaves on your plant is actually due to underwatering. This present soil is retentive, but if you water in small quantities or infrequently (or both), the water stays near the surface and roots get very little. While repotting, remove as much of original soil as possible (use your fingers to pry the roots away gently), give your plant a good drainage in new pot, sit it in firmly and DO NOT water for a couple of days after repotting. Good luck with you plant!