Missing cat

After the ordeal today, I felt a bit weak and decided to go to bed early and have some rest. After brushing my teeth I went to check on the cats as usual and could only find one. One? Then I did a search in all the places they like to hide. Twice. No success.

So I realized that she had perhaps jumped/fallen off the balcony. The other one. So went outside, and called her. No reply. Fortunately my neighbours downstairs were still awake, so rang their door. Searched their terrace and the surroundings, without result.

Sent an email to all the neighbours to keep a look-out. Called a friend who didn't answer. Just wanted to talk to somebody, but at this hour it's difficult. I don't want to disturb people.

At the same time, I'm extremely worried. I go out on the balcony every 5 minutes to see if she's there. I go outside the house to try and find her.

At this moment I don't know what to do. Is she hurt? Is she hiding 'cause of fear? Why doesn't she come when I call her?

Agony.