Recovering photo's and connecting to Macbook Pro

[Joy21]

I don't know what I did wrong, but I was getting rid of some unwanted applications and downloads in the Application manager under settings. A few hours later, I came back and all my files with photo's were gone from my gallery. I didn't uninstall any application to do with my gallery (to my knowledge) and have been searching for solutions online all day. I downloaded Kies and a photo recovery app for Samsung, but my phone doesn't come up as a USB device on my desktop (so I cannot scan it to restore files) although it says that it is connected as a media device in the notifications bar. Please help!:-\