I'm new too and experienced similar problems with my seedlings. They started out great the first week, but then slowed way down in week 2 and 3. Now I'm at day 40 and they are doing quite well.

It's easy to over water and/or over fertilize at this early stage. Weeds are predisposed to surviving in dryer conditions. They don't need as much water as us newbies think. Depending on the temperature in your tent/room, the plants could go a week or more without requiring water. The hotter the environment, the more water they'll need.

Speaking of temperature, the environment you're providing also contributes to the plants growth: light intensity, temperature, size of the pots, and humidity. All of those will contribute to growth. You may have to "dial everything in" to get the ideal environment, which includes how far above the plants your lights should be, which depends on the type of lights you're using.

Hang in there and good luck.

Thanks for the answer. I forgot to mention, these are outdoor on my balcony.

The same principle applies to outdoor potted plants, though you really need to pay attention to the forecasts. Outdoor potted plants are more susceptible to the sun's heat because the soil (and the plant's roots) are more exposed and can dry out much faster.

Your plants are a little bit small for day 14 but they don't look deformed. They may be stunted due to over watering.
Here's a picture of mine at day 14 and day 40

Yeah it's been 3 weeks and they are still the same size ... the weather has been bad here, whole week no sun and next week same thing.

I'm starting to think about putting a light over them outside. Would that be viable?

Ok guys I'm try putting a light over my last seedling, is this ok?

I'm not sure if the light should be straight up or sideways.