Stunting seeds

If they are auto flowers, the best thing to do is to sew them straight into your final growing medium in the final pot. Autos don't like too much stress, and tend to go at their own pace. I saw my first sprout at exactly 4 days after sewing and it looks fantastic.

What type of light are you using for the early stages? If you are using one main light (such as a HPS) for everything; this can be difficult to dial in the climate when plant is quite small. It may be better to setup a smaller (fish-tank size) veg zone with fluros. Like ChitownCannaChica says, dial in the climate and you have done the best you can. :) Good luck mate!

They take about two to three weeks to get bigger— out of the seedling phase. In the meantime, make sure your environment is spot on with heat, humidity, light distance, and not over/under watered

Hello. consider that it takes about two weeks before starting to grow well. At first it has less visual growth because the plant makes the roots work. Arrived in the settling phase you will see it grow much faster :) look at some diary in general to get an idea of the growth in the various stages of growth :) I hope I was helpful :)