No nutes for a while. wait till there are a couple sets of leaves and then start very lightly with nutes. If you can, get some nutes growers use. I rec Dyna-Gro but that is just me.
A light breeze is fine. You don't want wind to knock them down.
Get a reflector on the light. You are losing alot. Also better if bulb is sideways.
Yoy do not need larger pots yet and do not put two plants in one pot.
Also, and we all make this mistake, .....relax and try to focus on understanding and listening to the plant. When she needs nutes, she'll tell you. Right now the stretching is her telling you "more light please".
When it is time to repot, I use a mix of cheap (no added nutes) potting soil, peat moss, Perlite and vermiculite and then add 2T/ gal of lime. Works great! I get them all from local hardware store. Plain perlite is sometimes harder to find but garden shop ought to have it.