Sounds like a corrupt/bad/faulty SD card or possibly even a Fake SD card. A fake SD card is one that pretends to be a larger size than it really is, so that when you go over the actual size all the files begin to get corrupted, and you lose a lot of data. You'd be surprised at the places you can pick them up. If a price seems too good to be true, it probably is.
It may not be a fake one, as some SD cards are just faulty and need to be replaced under warranty.
Your best bet to recover the files is to insert the card into a card reader and use a file recovery tool on a PC. More than likely, you've already lost app data, as well as a lot of other stuff.
I wish I had better news.
08-03-2015 12:27 PM