Restoring an iPhone

I have the iPhone 5 and about once a month I sync it to my computer and back up the music, contacts, photos and whatever else I have saved on my phone. Today, I had to restore my phone and when I plugged it back in, the last back-up that it shows is from October 2013. I checked the iCloud back ups and my computer back ups and nothing is later than that. Is there any way to retrieve the later syncs that I had? I can't understand why they're not showing up as an option and it'd be incredibly helpful if I can find one from a later date!