@Cathy205:
It sounds like it is a browser issue.
1. Make sure your browser accepts the cookies on Airbnb's website.
2. Try using a different browser (fFrefox, Chrome, Internet Explorer, Opera, etc.).
3. If all else fails download the app to your cell and try uploading them via the phone then go back to your main computer to add in the captions.
Airbnb design team made some changes to the admin panel recently and the photo section has some serius bugs they have yet to fix.
Good luck!