You don't need the plastic cover over them. I would also move that light closer. about 2 or 3 inches from the plant. I am guessing thats a CFL daylight. Also you don't need any nutrients yet. They have all they need for a few weeks.

As for the shell. I would have used tweesers to get it off. The membrain sometimes gets stuck and you have to help it a bit. I don't know if you killed it yet just watch it and see.