Why does my IPhone keep deleting my notes?

I've never really had a lot of notes on the notes app but for some reason my phone keeps deleting them. It started out with two or three and now it's every single note I have. Some of which were important. I bought the iPhone 5 back in may or June and dropped it no more than five times. Is this a problem where I'd have to go to apple?

There could be a number of reasons; the first that comes to mind is do you have notes on to be synced in iTunes or iCloud?
Second thing that comes to mind, are you sure you are using Notes properly? Are you tapping done once you have completed the note?
You only have 90 days of Complimentary Phone Support unless you bought the Apple extended Care Plan, if not, they will charge you to go over this issue.
http://www.apple.com/...t-in-apps/
tells a little about the Notes App, but nothing in the way of troubleshooting.

Your best bet would be to search the Apple self help area: http://www.apple.com/...rt/iphone/