Cosmo was trying to hop over Lulu to get to a different perch, and the cage door was open (I was changing the water since Lulu pooped in it). Cosmo fell on the outside of the cage(not a bad fall, but enough for her to get startled), and started flying all over the room, smashing into windows. Thankfully she is finger trained, so I picked her up and put her back in. She's trembling all over right now, and she slammed pretty hard into the windows. I think it will take a while for her to stop being scared of the outside of the cage now (and since Lulu watched the whole thing, same for her). Will she be ok?
You'll need to keep an eye on her to ensure there wasn't any internal injury that you are unable to see.
Otherwise, just keep them quiet for a bit - play some music for them and talk to them quietly.
It will take some time for them to calm down but they should be fine.
They may well be afraid to come out of the cage for awhile so in the days to come, make sure you allow them to make that decision rather than trying to force either of them to do so.
Be sure to shut the curtains or blinds when they are out of the cage.