I don't know about leaves falling off (is that one in the bottom picture?), but those young tomato plants look pretty normal. If they used to be in smaller containers, those smaller containers may just have been too small, and stressed the plants. Those plastic cups in the picture right now are kind of marginally sized, so smaller ones must have been pretty undersized.

As to the rest, it depends. 7 hours/day under grow lights is kind of short. I'm assuming the grow light is just an inch or two above the plants. But they don't look like they are hungry for light. As to water, the soil should be slightly moist. Stick your finger in it. A few drops every two days won't do it. A quart every two days is too much.

I'm wondering is the planting soil isn't absorbing the water but rather shedding it. Have you tried submerging the pots in a bucket of water up to their rims and leaving them for about a half hour.... for the larger ones.... so the soil gets well hydrated? Then take them out and let them drain away all excess water?

Some people might think this is counter-intuative, but it is a problem I've had with some lighter-weight potting soils when they do get dried out.

I think the pictures may make the plants look better than they actually are for some reason. And by leaves falling off I guess I mean the bottom few leaves, like a whole off shoot. Not just individual leaves. And I should mention I only transfered a few plants to bigger pots some are still in the plastic cups. I was trying to experiment and see if that was the issue. I will try the submerging and see if it helps. Thank you for the suggestions so far!

They look pretty good to me! I have heard that putting them outside and bringing them in is not the best idea (although I usually do it). If there's a big temperature differential it might be difficult for them to adapt. I wouldn't worry too much about the lower leaves as they will be unnecessary anyway when it comes time to plant them deeply in the ground.

Before you spend time submerging, just poke your finger an inch into the soil. If it's moist, you're done.

Hmm that is really helpful. I'll definitely repot all the ones still in cups still. I definitely planted too early, its like spring will never come for Nebraska. It's my first time planting from seed so I'll remember that next season.

For small plants, when they get larger than the pot, it's past time to pot up.

Tomatoes are nutrient hogs. To grow in pots they have to be right sized. If they aren't outright dying, they may be OK until ready to plant outside. Tomatoes usually recover leaf growth when transplanted, if the roots are still healthy and they get put in a spot with good soil.

Any chance your water at your house is treated with water softener and has high salt content? I could not grow plants inside at my house until I got a rain barrel and saved water for over the winter. All the water at my house was treated with water softener, not good for plants long term due to salt content not being favorable for plant health.