Great advice above.. the chick with the eye problem, how is it’s eyes close. Are they matted/stuck closed. If so use a quip wet it with warm water and gently run it over its eyes.. that may help. With the cramped conditions that maybe causing the problems with its eyes not the brightness of the light.
You could also take a red sharpie marker and color the bulb, a lot safer than aluminum foil (that could even cause a fire). It’s not an ideal way to do it but it would work, especially since your limited on recourses at the time.
I agree bigger area for those babies. Taping two boxes together is a good idea if you have nothing else. I use a dog kennel for mine. Think outside the box look around the house and find something bigger that will work.