Yes, remove the danios and maybe some other fish and return them to the lfs as soon as you can. But for now they are better off staying in your tank. And for now I would do maybe a 10% water change every other day, so you don't shock your fish, and clean water is a powerful healer.
if I were you, I would just sit back, take a deep breath, and let things be for a while. Keep the lights in the room with the tank low, so you can see to the back of the tank but not much more. This will help stress. If you have aquarium salt this will help too. If not, just let things be for a while. Everything will be just fine.
Edit, forgot you had tetras. But since you don't have salt it doesn't make a difference. Good luck tomorrow, I would move the danios and maybe a few of your other fish you aren't too attached to back to the lfs. The rest might be just fine, if not, you've tried your best, and you can get things back up and running in no time. Fish keeping will teach you patience, I know i had none when I started! But you just gotta wait this one out.