Hey, friend! After experiencing mobile phone Micro SD card file loss problems, I know the deleted data off from memory card could be restored back with the help of deleted data recovery software before these original SD card photos are overwritten by new photos, files and the likes on the same memory card.
So, no matter what happens, always keep this SD card away from new stuffs and go try some photo recovery software.
Honestly, last time, I have read many related articles, posts and threads and learned this. Perhaps, you may also visit these posts and learn more detailed information like:
http://www.cgsecurity.org/wiki/TestDisk
http://en.wikipedia.org/wiki/Data_recovery
Or http://www.icare-recovery.com/howto/memory-card-photo-recovery.html
Timely back up all restored photos well on another memory card, flash drive or hard drive
