RANDOMLY DELETED PICTURES//PROBABLY A MEMORY PROBLEM??

My iPhone 5c randomly deleted ALL my photos, yet still says they're using up 27 GB of my memory. It won't let me view the pictures, even when plugged into a computer. I also was going to update my phone to 8.1.3 to see if that was part of the problem but it said I didn't have enough storage, and to be able to get more storage, I need to be able to view my photos and delete some. Is there a way to fix this without completely resetting my phone?